Herbicidal compositions and methods

ABSTRACT

Described are preferred methods and compositions for controlling weeds in soil that involve the use of a bleaching herbicide such as fluridone in combination with at least one other additional selected herbicidal agent, which is preferably a PPO-inhibitor such as fomesafen or flumioxazin. Also described are safening effects of bleaching herbicidal agents such as fluridone on other herbicides, and of other herbicides on bleaching herbicidal agents. Further described are methods and compositions for controlling weeds in soil that comprise the use of fluridone. Methods and compositions for controlling weeds in permanent crops are also described.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 14/332,036, filed Jul. 15, 2014 which is a continuation of International Application No. PCT/US2014/034526, filed Apr. 17, 2014 which claims the benefit of priority to U.S. Provisional Patent Application No. 61/813,166, filed Apr. 17, 2013 and to U.S. Provisional Patent Application No. 61/814,600, filed Apr. 22, 2013; this application also claims the benefit of priority to U.S. Provisional Patent Application No. 62/065,389 filed on Oct. 17, 2014; each of which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to herbicidal compositions and methods.

BACKGROUND

Herbicides have been widely used to kill unwanted plants or weeds in crop fields. Glyphosate, also called Roundup®, is a common agricultural herbicide. This herbicide class functions by blocking the shikimate pathway in plants. The use of glyphosate resistant crop strains, also known as Roundup Ready® crops, in conjunction with glyphosate herbicide has increased crop yields and reduced costs for farmers. The use of glyphosate dramatically decreased the reliance on preemergent or residual herbicides as most production agriculture transformed to using postemergent applied glyphosate only. However, the emergence of glyphosate resistant weeds presents a growing problem for farmers. Weeds not killed by glyphosate necessitate the use of additional or larger quantities of herbicides, as well as a decrease in use of no-till farming methods, both of which increase the cost of farming.

Another class of herbicides is called Protoporphyrinogen oxidase (PPO) inhibitors. Herbicides in this class block the oxidation of the protoporphyrinogen within the chloroplast of a plant cell. Oxidation of protoporphyrinogen is critical for the production of protoporphyrin IX, a precursor molecule necessary for the metabolic synthesis of chlorophyll (a component of photosynthesis) and heme (an element of electron chain transport). Examples of PPO inhibitors include acifluorfen, carfentrazone, flumioxazin, flumiclorac, fluthiacet, fomesafen, lactofen, oxyfluorfen, pyraflufen-ethyl, saflufenacil and sulfentrazone. In practice, PPO-inhibitors are generally not used as postemergent herbicides across a wide-range of crops due to the potential for injury or killing the crops. They have limited uses as a foliar spray, primarily as a defoliant or desiccant. PPO-inhibitors are primarily applied preplant, or used weeks before crops are planted, to avoid potential phytotoxicty on emerging crop seeds from the residual remaining in the soil. This interval between application and planting allows residues to degrade for greater crop safety. However, preplant applications also reduce the longevity of weed control after the crops are planted because the herbicide starts to lose activity as crops are planted. This necessitates the need for additional weed control measures after planting. Some PPO-inhibitors contain use directions that require rainfall following the application and before crops are planted to mitigate potential crop phytotoxicity. Thus, the use of PPO-inhibitors as preemergence herbicide just before, at, or immediately after planting is relatively limited, or very crop specific, due to significant concern over crop injury. Resistance to PPO inhibitors has been documented, but not at the magnitude of glyphosate resistance, causing farmers and industry alike to caution the repeated application of PPOs as a single chemistry herbicide.

Fluridone, 1-methyl-3-phenyl-5-[3-(trifluromethyl)phenyl]-4(1H)-pyridone, is a herbicide in the class of bleaching herbicides. Fluridone's mode of action inhibits the biosynthesis of carotenoid precursors. Carotenoid pigments protect chlorophyll from photodegredation. The inhibition of the synthesis of the precursors allows for the chlorophyll to become susceptible to degredation. Fluridone is commonly used in aquatic applications, and has also been used in agricultural settings, such as for controlling weeds in fields. Fluridone is sold under several trade names, including Brake™ (SePRO Corporation, Carmel, Ind.). Fluridone is a relatively broad spectrum herbicide that cannot be used in many crops due to the potential for phytotoxicity. However, cotton is one crop that is quite tolerant to fluridone.

In view of this background, need remains in the area of improved herbicidal methods and compositions useful for controlling weeds, particularly in an agricultural context.

SUMMARY

In one aspect, the present invention provides for improved methods and compositions for controlling weeds, for example in an agricultural setting. Such weeds can be, for example, but is not limited to, Amaranthus palmeri (optionally glyphosate resistant), also called Palmer amaranth, Palmer pigweed or P. amaranth, in cotton or other field crops. Other agricultural crops suitable for methods of the current invention include sweet potatoes, broccoli, peanuts, melons, soybeans, sunflower, dry beans, rice, corn, fruit, nuts, grapes, tree, or vine crops. These or other crops can be generated from any suitable plant-generating material including for example seeds, tubers, slips, seed plants, roots or other plant parts, and the like.

In another aspect, the present invention provides herbicidal methods and compositions that include a bleaching herbicide, or phytoene desaturase inhibiting herbicide (PDS-inhibitor), such as fluridone, norflurazon or another phytoene desaturase inhibiting herbicide (PDS-inhibitor), and a second herbicide, such as a PPO-inhibitor herbicide. Preferably, the PPO-inhibitor or other second herbicide does not require water, or requires lower amounts of water than the first herbicide (e.g. bleaching herbicide), for activation. Herbicides used in embodiments of the present invention may be used as salts and/or esters in addition to use in their free acid or free base form.

In additional aspects, fluridone has unexpectedly been found to safen or reduce the damage caused to a plant by a second herbicide, in particular where the plant exhibits a significant phyotoxic response to the second herbicide. As well, other herbicides have been found to safen or reduce the damage caused to a plant by fluridone, in particular where the plant exhibits a significant phytotoxic response to fluridone. Safeners generally reduce the effect of the herbicide on crop plants and/or improve the selectivity between crop plants as compared to the weed or weeds being targeted by the herbicide. Suitable second herbicides of the present invention for use with fluridone, or with other similar bleaching herbicides, include but are not limited to acetochlor, acifluorfen, carfentrazone, dicamba, diuron, flumiclorac, fluthiacet, fluometuron, flumioxazin, fomesafen, lactofen, metolachlor, oxyfluorfen, pendimethalin, pyraflufen-ethyl, pyrithiobac-sodium, pyroxasulfone, saflufenacil or sulfentrazone. In certain preferred embodiments, the second herbicide that is safened by fluridone, or another bleaching herbicide, is fomesafen or flumioxazin, especially in cotton plants. In additional preferred embodiments, the second herbicide that safens fluridone, or another bleaching herbicide, is flumioxazin or fomesafen, especially in soybean plants. Fluridone may also safen other herbicides used, and when two herbicides are used in combination, they may safen each other.

In still other aspects, it has been found, that fluridone, a herbicide commonly used in aquatic applications, also has surprisingly beneficial uses in controlling weeds in permanent crop applications. Permanent crops are those crops produced from plants which typically last for more than one season and therefore do not need to be replanted every growing season like seasonal crops do. Permanent crops include, but are not limited to trees, nuts, and/or vine crops. When fluridone is used for controlling weeds in permanent crop applications, it may be desirable to maintain moisture in the soil where permanent crops reside. Water or moisture may be provided to the soil where permanent crops reside by any suitable method, including but not limited to irrigation. Applicants have discovered that, surprisingly, regular and substantial irrigation regimes used in permanent crop applications dramatically increase the duration of weed control provided by fluridone, making fluridone particularly useful as a preemergent herbicide in permanent crop plant applications such as the cultivation of fruit trees, nut trees, and/or vines.

For example, fluridone may be used to control weeds in crops of trees, nuts, and/or vines. In some particular embodiments, fluridone may be used to control weeds in crops of almond (including for example sweet almond), pecan, pistachio, walnut, apple, pear, apricot, cherry, nectarine, peach, plum, prune, avocado, citrus (including for example grapefruit and orange, e.g. “cara cara” orange (Citrus sinensis)), date, fig, grape (including for example “Thompson” grape (Vitis vinifera)), kiwi, olive, peanut, pomegranate, potato, sweet potato, pome, stone fruit, and/or tobacco.

Fluridone, alone or in combination with one or more other herbicides as discussed herein, may be used to control various weeds, including but not limited to, fiddleneck, redmaid, horseweed, barnyard grass, common purslane, prickly lettuce, witchgrass, prostrate spurge, hairy fleabane, and/or yellow nutsedge. This weed can control can, in certain embodiments, occur in conjunction with the growth of permanent crop plants.

Additional embodiments of the invention, as well as features and advantages thereof, will be apparent from the descriptions herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B shows digital images of field treatments at various active ingredient (ai) application rates. No difference was seen between treatments due to ideal growing and optimal herbicide efficacy conditions. No phytotoxicity was seen at any treatment. All exhibited great control compared to the untreated control. Top pictures were taken one week post treatment (wpt) and bottom image was taken at 9 wpt. Digital image A.1. shows a field 1 wpt where Brake was applied at the rate of 0.2 lb ai/A. Digital image A.2. shows a field 1 wpt where BrakeF2 was applied (0.2:0.125 lb/ai/A). Digital image A.3. shows a field 1 wpt where Fomesafen was applied at the rate of 0.2 lb ai/A. Digital image B.1. shows a field 9 wpt where Brake was applied at the rate of 0.2 lb ai/A. Digital image B.2. shows a field 9 wpt where BrakeF2 was applied (0.2:0.125 lb/ai/A). Digital image B.3. shows a field 9 wpt where Fomesafen was applied at the rate of 0.2 lb ai/A.

FIG. 2 shows digital images of cotton, taken 7 weeks post treatment. Treatment application was applied by backpack sprayer. At the rate of 0.4:0.4 lbs ai per acre (ai/A) there was phytotoxicity visible on the first true leaves of the cotton, however, plants grew out of this. Plots were overseeded with P. amaranth and both ratios completely controlled P. amaranth growth in the treated areas. Digital image A shows a field 7 wpt where 0.2:0.2 lb ai per acre fluridone:fomesafen was applied. Digital image B shows a field 7 wpt where 0.4:0.4 lb ai per acre fluridone:fomesafen was applied.

FIG. 3A and FIG. 3B shows digital images from a greenhouse trial. UTC is “untreated control.” Brake is fluridone. BrakeF2 is fluridone plus fomesafen. Growth of treated cotton plants 4 weeks after planting (FIG. 3A) is shown. Fomesafen has a stunting effect on cotton. Brake F2 is able to safen fomesafen. Digital images in FIG. 3A shows a series of cotton plants 4 weeks after planting. A.1. is untreated control (UTC). A.2. is Brake 0.2 lb ai/A. A.3. is Fomesafen 0.125 lb ai/A. A.4. is fomesafen 0.2 lb ai/A. A.5. is Brake F2: Brake 0.2 lb ai/A with Fomesafen 0.125 lb ai/A. FIG. 3B shows digital images B which show a series of cotton plants 4 weeks after planting. B.1. and B.2. are untreated controls. B.3. and B.4. are Brake 0.2 lb ai/A. B.5. and B.6 are Fomesafen 0.2 lb ai/A. B.7 and B.8 are BrakeF2.

FIG. 4 shows digital images of a demonstration of the safening effect of fluridone on herbicides. The pot on the left was treated with a herbicidal mixture of fluridone and flumioxazin. The pot on the right was treated with flumioxazin only and shows damage to cotton plant.

FIG. 5 shows digital images of the safening effect of the mixture of fluridone and flumioxazin in soybean.

FIG. 6 shows digital images of soybean plants treated with various quantities of fluridone and flumioxazin when applied pre-plant. 6.1. is 0.2 lb/A fluridone+0.008 lb/A of flumioxazin. 6.2. is 0.2 lb/A fluridone+0.016 lb/A of flumioxazin. 6.3. is 0.2 lb/A fluridone+0.128 lb/A of flumioxazin. 6.4. is 0.2 lb/A fluridone+0.17 lb/A of flumioxazin. 6.5 is untreated control (UTC).

FIG. 7 show the percentage of chlorosis observed on soybean plants treated with fluridone and flumioxazin when applied pre-plant. UTC is untreated control.

FIG. 8 shows the percentage of leaves including cotyledon, unifolate, and/or trifoliate leaves with visible bleaching observed on soybean plants treated with fluridone and flumioxazin when applied pre-plant.

FIG. 9 shows the height of soybean plants 9 days after treatment with herbicide compositions comprising fluridone; flumioxazin; as well as compositions with various ratios of fluridone and flumioxazin.

FIG. 10 shows the percentage of chlorosis observed in soybean plants treated with herbicidal compositions.

FIG. 11 shows the percentage of chlorosis observed in soybean plants treated with herbicidal compositions.

FIG. 12 shows digital images of cotton plants 16 days after treatment with herbicidal compositions comprising fluridone and fomesafen. 12.1 is untreated control (UTC). 12.2 is 0.25 lb ai/A fomesafen. 12.3 is 0.1 lb ai/A fluridone+0.25 lb ai/A fomesafen.

FIG. 13 shows the height of cotton plants 16 days after treatment with herbicidal compositions.

FIG. 14 shows the height of cotton plants 29 days after treatment with herbicidal compositions.

FIG. 15 shows the height of cotton plants treated with various rates of flumioxazin.

FIG. 16 shows digital images of cotton plants treated with flumioxazin. 16.1. is 0.0125 lb ai/A flumioxazin. 16.2. is 0.025 lb ai/A flumioxazin. 16.3. is 0.05 lb ai/A flumioxazin. 16.4. is 0.1 lb ai/A flumioxazin.

FIG. 17 shows the crop stand, which is the number of viable plants, for cotton plants treated with herbicidal compositions.

FIG. 18 shows a digital image where cotton plants were various treatments were applied to cotton plants. One set of cotton plants were treated with flumioxazin at the rate of 0.05 lb/A (18.1.), one set of plants was treated with a combination of flumioxazin at 0.05 lb/A and fluridone at 0.2 lb/A (18.2.), and one set was left untreated as an untreated control (18.3., UTC).

FIG. 19 shows the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury measured 26 days after treatment.

FIG. 20 shows the growth stage of cotton plants 26 days after treatment.

FIG. 21 shows the damage to cotton plants 16 days after treatment with herbicidal compositions.

FIG. 22 shows the damage to cotton plants 21 days after treatment with herbicidal compositions.

FIG. 23 shows three digital images of cotton plants treated with herbicidal compositions. 21.1. is untreated control (UTC). 23.2. is fomesafen 0.375 lb ai/A. 23.3. is Fomesafen+Fluridone 0.375:0.2 lb ai/A.

FIG. 24 shows the percent chlorosis observed 21 days after treatment of soybean plants with herbicidal compositions.

FIG. 25 shows a series of digital images of soybean plants treated with herbicidal compositions. 25.1. is untreated control (UTC). 25.2. is Fluridone 0.1 lb ai/A. 25.3. is Fluridone 0.1 lb ai/A+Flumioxazin 0.05 lb ai/A. 25.4. is Fluridone 0.1 lb ai/A+Flumioxazin 0.1 lb ai/A. 25.5. is Fluridone 0.1 lb ai/A+Flumioxazin 0.15 lb ai/A.

FIG. 26 shows the percentage of leaves with visible bleaching injury (% PHYBLE) when various herbicidal compositions are applied to corn plants.

FIG. 27 shows a digital image of corn plants when various herbicidal compositions are applied. 27.1. is Fluridone 0.05 lb ai/A. 27.2. is Fluridone 0.1 lb ai/A. 27.3. is Fluridone 0.15 lb ai/A. 27.4. is Fluridone 0.05 lb ai/A+Flumioxazin 0.05 lb ai/A. 27.5. is Fluridone 0.1 lb ai/A+Flumioxazin 0.1 lb ai/A. 27.6. is Fluridone 0.15 lb ai/A+Flumioxazin 0.15 lb ai/A.

FIG. 28 shows the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury observed on cotton plants when various herbicidal compositions are applied.

FIG. 29 shows digital images of corn plants when various herbicidal compositions are applied.

FIG. 30 shows Crabgrass sp., yellow nutsedge, and hairy fleabane control 184 days following PRE applications of fluridone and flumioxazin in a Kerman, Calif. almond orchard. Values with the same letter for each weed specie are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 31 shows hairy fleabane control following PRE applications of fluridone and flumioxazin in a Shafter, Calif. almond orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 32 shows yellow nutsedge control following PRE applications of fluridone and flumioxazin in a Shafter, Calif. almond orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 33 shows spotted spurge control following PRE applications of fluridone and flumioxazin in a Shafter, Calif. almond orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 34 shows sprangletop control 211 days following PRE applications of fluridone and flumioxazin in a Shafter, Calif. almond orchard. Values with the same letter are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 35 shows fiddleneck, redmaids, and Canadian horseweed control 58 days following PRE applications of fluridone and flumioxazin in a Kerman, Calif. vineyard. Values with the same letter for each weed specie are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 36 shows barnyardgrass, common purslane, and prickly lettuce control 155 days following PRE applications of fluridone, flumioxazin, and indaziflam in a Kingsburg, Calif. vineyard. Values with the same letter for each weed specie are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 37 show switchgrass plant counts following PRE applications of fluridone and indaziflam in an Elderwood, Calif. orange orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 38 shows prostrate spurge plant counts per plot following PRE applications of fluridone and indaziflam in an Elderwood, Calif. orange orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 39 shows percent weed density following PRE applications of fluridone and indaziflam in an Elderwood, Calif. orange orchard. Values with the same letter for each evaluation date are not statistically different according to Fisher's Protected LSD (α=0.05).

FIG. 40 shows preemergence Palmer amaranth control following fluridone application to a coarse sand soil under varying amounts of irrigation in a greenhouse. These data suggest that increasing the amount of irrigation, increases preemergent control.

FIG. 41 shows preemergence Palmer amaranth control in dryland cotton and total weed control in irrigated walnut following fluridone application.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to certain embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications, and such further applications of the principles of the invention as described herein being contemplated as would normally occur to one skilled in the art to which the invention relates.

As discussed above, certain aspects of the present invention relate to methods and compositions involving the use of a bleaching herbicide, such as fluridone, diflufenican, picolinafen, beflubatamid, flurochloridone, flurtamone, fluometuron, and/or norflurazon, alone and/or in combination with certain other herbicidal agents, especially PPO-inhibitors, for controlling weeds including but not limited to glyphosate resistant weeds in an agricultural setting. The two herbicides in combination can provide enhanced control of weeds and/or improved safety to the crop when applied for example before the emergence of plants from seeds or another plant-generating material, for instance applied in pre-planting or pre-emergent fashion. This enhanced control can for example be achieved under initial dry conditions after planting when little or no water is added to the soil (e.g., in the form of rainfall and/or by irrigation).

As used in this specification, and unless otherwise indicated, the term “herbicide” refers to a molecule or combination of molecules that retards or otherwise kills undesirable, unwanted plants such as, but not limited to, deleterious or annoying weeds, broadleaf plants, grasses, and sedges; and may be used in this manner for crop protection. “Herbicide” also refers to any salt and/or ester forms of a herbicide as well as the free acid or free base form of the herbicide. The phrase “effective amount” means an amount of herbicide necessary to produce an observable desired effect to reduce unwanted plant growth, including the effects of plant necrosis, plant death, growth inhibition, reproduction inhibition, inhibition of proliferation, and removal, destruction, or otherwise diminishing the occurrence and activity of undesirable, unwanted plants. Undesirable, unwanted plants include herbicide-tolerant or herbicide-resistant weeds such as glyphosate-tolerant weeds. The term “chlorosis” means a condition where plant leaves produce insufficient chlorophyll. There are many ways to measure and/or assess damage to a plant, for example the number or percentage of all leaves with visible bleaching injury may be measured and/or calculated (PHYBLE) as a measure of chlorosis. In addition, or alternatively, the number or percentage of cotyledons with excessive wrinkling and/or brown spotting due to herbicidal injury (PHYGEN) may be measured and/or calculated as a measure of injury to the plant.

Cotton (Gossypium spp.) is the world's most important textile fiber crop and is one of the world's most important oilseed crops. Cotton plants provide a source of human food, livestock feed, and raw material for industry. Cottonseed is pressed for cooking oil and the residual cottonseed meal is used for animal feed. Industrial uses of cotton include candlewicks, twine, paper and a multitude of fabric products. The genus Gossypium is very large, containing about 50 species. Two tetraploid species of Gossypium have spinnable seed fibers called lint. These two species are G. hirsutum (referred to as American Upland cotton) and G. barbadense (referred to as Pima cotton).

Cotton is a dichotomous plant with perfect flowers, i.e., cotton has male, pollen-producing organs and separate female, pollen-receiving organs on the same flower. The cultivated cotton flower is surrounded by three triangular bracts forming what is commonly known as squares. The flower contains an open corolla with five petals, a staminal column bearing clusters of stamens and forming a tube that encloses the style. The compound pistil consists of three to five carpels with stigmas protruding above the anthers. The ovary develops into a three- to five-loculed capsule or boll. From seven to nine seeds are set within each lock or locule. On the day preceding anthesis, a twisted corolla emerges from the square. On the day of anthesis, the corolla opens and pollen shedding occurs. The corolla turns red the day following anthesis and later falls from the plant. Pollination occurs with the opening of the anthers and shedding of pollen on the stigma or with the deposit of pollen on the stigma by insects.

Cotton is slow growing by nature, often times more similar to trees than other important agronomic crops. It requires hot weather to grow, delaying the majority of its growth until later in the season. The majority of weeds, or unwanted plant material, are not restricted by these weather constraints. This puts cotton at a disadvantage over a large number of weeds, which are fast growing and can often out compete cotton early in the season. Thus it is essential that herbicides are included in any cotton program. Unfortunately, due to a number of reasons, mostly economical, there are a limited number of herbicides that are used in weed control for cotton, and a number of weeds have developed resistance to some chemistries that are available to cotton growers, in particular, glyphosate.

One of the most impactful glyphosate-resistant weeds that farmers face is P. amaranth. A survey taken by Southwest Press states that over 50% of American Upland cotton contains resistant P. amaranth. In response to this epidemic, farmers have increased usage of other chemistries, which has led to nearly a doubling of the cost of chemical input per acre. A number of growers have resorted to wicking, or hand hoeing the plants out, at a much more significant cost of chemical and labor.

Herbicides describe below may be used in embodiments of the present invention in their free acid or free base form as well as the salt, for example sodium salt, and/or ester derivatives.

In certain embodiments of the present invention, fluridone can be applied to soil at a rate of up to about 0.5 pounds per acre and/or 0.4 pounds per acre, for example in the range of about 0.05 pounds per acre to about 0.5 pounds per acre and/or about 0.05 pounds per acre to about 0.4 pounds per acre. In other embodiments, fluridone can be applied to soil at a rate of about 0.1 pounds per acre to about 0.4 pounds per acre. In another embodiment, fluridone can be applied to soil at a rate of about 0.2 pounds per acre to about 0.4 pounds per acre. In still another embodiment, fluridone can be applied to soil at a rate of about 0.3 pounds per acre to about 0.4 pounds per acre.

In certain work to date, fomesafen was evaluated for use with fluridone either in a combination application or as sequentially applied. A product including a mixture of fluridone and fomesafen was designated as the Brake F2™ product. Fomesafen is a member of the PPO inhibitor herbicide class and may be applied pre-plant, pre-emergence or post-emergence (which can be conducted through post-directed spraying to avoid contact with the plant leaves) commonly for control or suppression of broadleaf weeds, grasses and sedges. Fomesafen has the chemical name 5-[2-chloro-4-(trifluoromethyl)phenoxy]-N-(methylsulfonyl)-2-nitrobenzamide and may also be used as the sodium salt thereof. In one embodiment, fomesafen may be applied in concert with fluridone at a ratio in the range of about 0.1:1 w/w (fluridone:fomesafen) and/or about 0.5:1 to about 10:1 w/w (fluridone:fomesafen), or about 0.75:1 w/w (fluridone:fomesafen) to about 10:1 w/w (fluridone:fomesafen). In another embodiment, fomesafen may be applied in concert with fluridone at a ratio in the range of about 0.75:1 w/w (fluridone:fomesafen) to about 8:1 w/w (fluridone:fomesafen). In still another embodiment, fomesafen may be applied in concert with fluridone at a ratio in the range of about 0.75:1 w/w (fluridone:fomesafen) to about 5:1 w/w (fluridone:fomesafen). In more preferred embodiments, fomesafen may be applied in concert with fluridone at a ratio in the range of about 0.75:1 w/w (fluridone:fomesafen) to about 4:1 w/w (fluridone:fomesafen). In these applications, embodiments include those in which the fluridone is applied at any of the rates (pounds per acre) specified herein. In still another embodiment, fluridone can be used in as low of a ratio as about 0.1:0.1 w/w (fluridone:fomesafen).

The combination of herbicides can provide enhanced control of weeds, including for example, Palmer amaranth, as compared to a corresponding treatment using fluridone alone. This enhanced control as compared to fluridone alone can be observed particularly under conditions in which the soil receives little or no water (e.g., in the form of rainfall and/or irrigation) in the period immediately following (e.g., two weeks following) application of the combination. Fluridone requires more moisture for activation than some of the other soil applied herbicides for activation, and thus under such relatively dry initial conditions the fomesafen can help to prevent weed breakthrough. This same effect can be provided in other selected combinations of fluridone or another bleaching herbicide such as norflurazon with fomesafen or other PPO herbicides.

Unexpectedly also, it has been observed that fluridone has a safening effect on fomesafen, flumioxazin and/or other herbicides. Herbicides may alternatively may have a safening effect on fluridone, or two herbicides may safen each other in certain applications. This affect was measured by observing the size and height of plants as well as lack of stunting to the cotyledon, and lack of spots or other phytotoxic symptoms (such as chlorosis, necrosis, and other visual injury) on the leaves of plants. This affect can be observed in FIGS. 3A and 3B. In FIG. 3A, the pot on the far right shows a cotton plant treated with both fluridone and fomesafen. The pots to the left show cotton plants that were not treated with any herbicide as a control as well as plants treated with fluridone only and fomesafen only. The cotton plant treated with both fluridone and fomesafen is larger than the pots to the left by visual inspection.

Other PPO inhibitor herbicides can be used instead of or in addition to the fomesafen, in additional embodiments.

Flumioxazin is another herbicide member of the PPO-inhibitor class that is commonly applied pre-emergent to control weeds, and has the chemical name 2-[7-fluoro-3,4-dihydro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazin-6-yl]-4,5,6,7-tetrahydro-1H-isoindole-1,3(2H)-dione. In certain embodiments of the present invention, flumioxazin can be applied to soil at a rate of about 0.015 pounds per acre to about 0.25 pounds per acre. In other embodiments, flumioxazin can be applied to soil at a rate of about 0.03 pounds per acre to about 0.25 pounds per acre. In another embodiment, flumioxazin can be applied to soil at a rate of about 0.3 pounds per acre to about 0.2 pounds per acre. In applicants work, fluridone has exhibited a safening effect on flumioxazin in cotton. In certain embodiments, flumioxazin may be applied in concert with fluridone at a ratio in the range from about 15:1 w/w fluridone:flumioxazin to about 1:5 w/w fluridone:flumioxazin. FIG. 4 shows this safening effect. The pot on the left of FIG. 4 shows three cotton plants treated with both fluridone and flumioxazin. The pot to the right of FIG. 4 shows cotton plants treated only with flumioxazin, and although three cotton plants were planted, only one emerged from the soil and did so with significant damage to the plant as seen by the brown spots on the leaves.

Acifluorfen is a member of the PPO inhibitor herbicide class, and has the chemical name, 5-[2-Chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid. Acifluorfen is effective against broadleaf weeds and grasses and is used agriculturally on fields growing soybeans, peanuts, peas, and rice. In certain embodiments, acifluorfen is applied in concert with fluridone as disclosed herein.

Carfentrazone is a selective broadleaf herbicide member of PPO inhibitor herbicide family with a triazolinone moiety, and has the chemical name (RS)-2-chloro-3-{2-chloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-fluorophenyl}propionic acid. In certain embodiments, carfentrazone is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Flumiclorac is a selective herbicide of the PPO inhibitor class for post emergence control and suppression of susceptible broadleaf weeds commonly used in corn and soybean fields, and has the chemical name [2-chloro-4-fluoro-5-(1,3,4,5,6,7-hexahydro-1,3-dioxo-2H-isoindol-2-yl)phenoxy]acetic acid. In certain embodiments, flumiclorac is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Fluthiacet or fluthiacet-methyl is a member of the PPO inhibitor class, and is commonly applied to actively growing weeds in soybeans to control annual broadleaf weeds, is particularly effective in controlling velvetleaf, and has the chemical name acetic acid[[2-chloro-4-fluoro-5-[(tetrahydro-3-oxo-1H,3H-[1,3,4]thiadiazolo[3,4-α]pyridazin-1-ylidene)amino]phenyl]thio]-methyl ester. In certain embodiments, fluthiacet is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Lactofen is a member of the PPO inhibitor herbicide class and is generally applied post-emergence, and has the chemical name ethyl O-[5-(2-chloro-α,α,α-trifluoro-p-tolyloxy)-2-nitrobenzoyl]-DL-lactate. In certain embodiments, lactofen is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Oxyfluorfen is a diphenyl-ether member of the PPO inhibitor herbicide class used for broad spectrum pre- and post-emergent control of annual broadleaf and grassy weeds in a variety of tree fruit, nut, vine, and field crops. Oxyfluorfen has the chemical name 2-chloro-α,α,α-trifluoro-p-tolyl 3-ethoxy-4-nitrophenyl ether. In certain embodiments, oxyfluorfen is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Sulfentrazone is a member of the PPO inhibitor herbicide class, and has the chemical name 2′,4′-dichloro-5′-(4-difluoromethyl-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl)methanesulfonanilide. Sulfentrazone is primarily taken up by the roots of treated plants. Plants emerging from treated soil turn necrotic and die after exposure to light. Foliar contact causes rapid desiccation and necrosis of exposed plant tissue. Shoot-root soil placement studies indicate that sulfentrazone is primarily absorbed by the roots of the plant following soil applications. In certain embodiments, sulfentrazone is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Pyraflufen-ethyl is a member of the PPO inhibitor herbicide class that inhibits protoporphyrinogen IX oxidase that is normally applied post emergence to broad leaved weeds, and has the chemical name ethyl [2-chloro-5-(4-chloro-5-difluoromethoxy-1-methylpyrazol-3-yl)-4-fluorophenoxy]acetate. In certain embodiments, pyraflufen-ethyl is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Pyroxasulfone is a residual herbicide and is considered to be a seedling shoot growth inhibitor, and has the chemical name 3-[5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)pyrazol-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole. In certain embodiments, pyroxasulfone is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Saflufenacil is another residual herbicide. In certain embodiments, saflufenacil is applied in concert with fluridone or another bleaching herbicide as disclosed herein. Saflufenacil can be applied sufficiently in advance of planting to avoid or essentially avoid crop injury, for example in certain aspects at least about 42 days in advance of planting.

Acetochlor is a member of the chloroacetanilide herbicide family, and has the chemical name 2-Chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)acetamide. Acetochlor is commonly applied preemergence or as a preplant incorporated herbicide. In certain embodiments, acetochlor is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Dicamba is a selective herbicide in the chlorophenoxy family of chemicals, and has the chemical name 3,6-dichloro-2-methoxybenzoic acid. Dicamba is a growth hormone or auxin. These hormones help to control plant growth. When plants are treated with dicamba, they grow in abnormal and uncontrollable ways, and often, the plants die. Dicamba is commonly used on many broadleaf weeds and woody plants. In certain embodiments, dicamba is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Diuron, also called DCMU, has the chemical name 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Diuron is a very specific and sensitive inhibitor of photosynthesis. It blocks the plastoquinone binding site of photosystem II, disallowing the electron flow from where it is generated, in photosystem II, to plastoquinone. In certain embodiments, diuron is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Fluometuron is a bleaching herbicide that is believed to inhibit photosynthesis and of carotenoid biosynthesis. Fluometuron has the chemical name 1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea. Commonly fluometuron is used as a herbicide in cotton and sugarcane fields as a preplant, pre-emergence, and post-emergence herbicide for the control of broadleaf weeds and annual grasses. In certain embodiments, fluometuron is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Metolachlor is a member of the shoot growth inhibitor herbicide class, and has the chemical name 2-chloro-N-(6-ethyl-o-tolyl)-N-[(1RS)-2-methoxy-1-methylethyl]acetamide. In certain embodiments, metolachlor is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Pendimethalin is an herbicide used in preemergence and postemergence applications to control annual grasses and certain broadleaf weeds. It inhibits cell division and cell elongation, and has the chemical name N-(1-ethylpropyl)-2,6-dinitro-3,4-xylidine. In certain embodiments, pendimethalin is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Pyrithiobac and the sodium salt thereof is a member of the ALS inhibitor herbicide class, and has the chemical name 2-chloro-6-(4,6-dimethoxypyrimidin-2-ylthio)benzoic acid. In certain embodiments, pyrithiobac or its sodium salt is applied in concert with fluridone or another bleaching herbicide as disclosed herein.

Other PPO-inhibitors that may also be used in embodiments of the present invention include, but are not limited to, bifenox, chlomethoxyfen, fluoroglycofen-ethyl, halosafen, fluazolate, cinidon-ethyl, thidiazimin, oxidiazon, oxadiargyl, azafenidin, pentoxazone, benzfendizone, butafenacid, pyraclinil, profluazol, and/or flufenphyr-ethyl.

Indaziflam is a member of the cellulose biosynthesis inhibitors class. This family of herbicides affects the assembly or the deposition of cellulose in a plant or crop plant. Indaziflam has the chemical name N-[(1R,2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1-yl]-6-[(1RS)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine, and may be used in the free base form, as the corresponding salt form, and/or a mixture of free base form and corresponding salt form.

Herbicides used in embodiments of the present invention may be used as their free acid or free base forms. Derivatives of herbicides may also be used, for example herbicides may be used as salts, for example but not limited to sodium salts, and/or esters of the herbicide.

In other aspects of applicants work to date, flumioxazin and fomesafen have demonstrated safening effects on fluridone in soybeans. Thus, it has been demonstrated that in plants, such as soybeans, that exhibit significant phytotoxic response to fluridone or other similar bleaching herbicides, a second herbicide can be included to safen the use of the bleaching herbicide. This evidences a very unique safening interaction of fluridone plus PPO-inhibitors by crop species without the interaction causing a similar safening effect on the weed. The second herbicide can be one of those second herbicides identified herein, including more particularly a PPO inhibitor herbicide in some embodiments, or specifically flumioxazin or fomesafen in further embodiments. FIG. 5 illustrates the safening effect of the fluridone and flumioxazin combination on soybean. The pot on left shows that fluridone alone on soybean causes bleaching to the cotyledon. The pot on the right, soybeans were treated with both fluridone and flumioxazin, with the resulting plants having no bleaching, while still maintaining significant weed control.

It has been observed that fluridone may cause chlorosis in soybean plants when used alone. Combinations of fluridone and flumioxazin may reduce the chlorosis observed in soybean plants.

It has also been observed that fomesafen and flumioxazin cause damage to cotton plants when used alone. Also observed was the unexpected benefit that fluridone safens fomesafen when used in combination and that fluridone safens flumioxazin when used in combination on cotton plants.

In still other aspects of the present invention, flumioxazin has been observed to safen fluridone when applied in combination with fluridone to corn plants. In one particular embodiment, flumioxazin was observed to safen fluridone as measured by the percentage of all leaves with visible bleaching injury (% PHYBLE) which is a measure of chlorosis. Compositions and methods that may exhibit this safening affect include, compositions comprising fluridone and/or flumioxazin, and application rates of from about 0.05 pounds per acre (1b/A) to about 0.15 lb/A, and/or from about 0.05 pounds per acre (1b/A) to about 0.2 pounds per acre (1b/A). In such embodiments, fluridone and/or flumioxazin may be applied separately and/or together.

In still other aspects, it has been found, that fluridone, a herbicide commonly used in aquatic applications, also has surprisingly beneficial uses in controlling weeds in permanent crop applications. Permanent crops are those crops produced from plants which typically last for more than one season and therefore do not need to be replanted every growing season. This is in contrast to seasonal crops which do need to be replanted each growing season. Permanent crops include, but are not limited to trees, nuts, and/or vine crops.

For example, fluridone may be used to control weeds in crops of trees, nuts, and/or vines. In some particular embodiments, fluridone may be used to control weeds in crops of almond, pecan, pistachio, walnut, apple, pear, apricot, cherry, nectarine, peach, plum, prune, avocado, citrus, date, fig, grape, kiwi, olive, peanut, pomegranate, potato, sweet potato, pome, stone fruit, and/or tobacco whether such crops are permanent crops, or whether such crops are seasonal crops.

Additional herbicides may be applied in combination with, prior to, and/or subsequent to application of herbicides including, but not limited to, fluridone. For example, other herbicide classes that may be used in methods of certain embodiments of the present disclosure include PPO-inhibitors, cellulose inhibitors, acetolactate synthase (ALS) inhibitors, acetyl coenzyme A carboxylase (ACCase) inhibitors, mitosis inhibitors, photosystem II (PSII) inhibitors, long-chain fatty acid inhibitors, and/or a combination thereof. Suitable additional herbicides include, for example, but are not limited to, 2,4-dichlorophenoxyacetic acid (2,4-D), acetochlor, acifuorfen, carfentrazone, clethodim, dicamba, dichlobenil, diquat, diuron, fluazifop, flumiclorac, fluthiacet, fluometuron, flumioxazin, fomesafen, glufosinate, glyphosate, halosulfuron, indaziflam, isoxaben, lactofen, metolachlor, napropamide, oryzalin, oxyfluorfen, paraquat, pendimethalin, penoxsulam, pronamide, pyraflufen-ethyl, pyrithiobac, pyrithiobac-sodium, pyroxasulfone, rimsulfuron, safufenacil, sethoxydim, simazine, sulfentrazone, a salt or ester thereof, and/or a combination thereof. Such additional herbicides may be applied preplant, postplant, preemergence, and/or postemergence of the crop and/or the weed to be controlled. Suitable PPO-inhibitors for use in embodiments of the present disclosure include, but are not limited to, flumioxazin, saflufenacil, p-ethyl, carfentrazone, sulfentrazone, pyroxasulfone, fomesafen, lactofen, acifluorfen, flumiclorac, oxygluorfen, and/or combinations thereof.

Suitable ACCase inhibitors for use in embodiments of the present disclosure include, but are not limited to, clethodim, fluazifop, sethoxydim, and/or a combination thereof.

Suitable ALS inhibitors for use in embodiments of the present disclosure include, but are not limited to, halosulfuron, rimsulfuron, penoxsulam, and/or a combination thereof.

Suitable mitosis inhibitors for use in embodiments of the present disclosure include, but are not limited to, pendimethalin, oryzalin, and/or a combination thereof.

Suitable PSII inhibitors for use in embodiments of the present disclosure include, but are not limited to, simazine, diuron, and/or a combination thereof.

Suitable long chain fatty acid inhibitors for use in embodiments of the present disclosure include, but are not limited to napropamide.

Suitable cellulose inhibitors for use in embodiments of the present disclosure include, but are not limited to, dichlobenil, isoxaben, indaziflam, and/or a combination thereof.

When fluridone is used in the methods of the present disclosure, any herbicidally effective quantity of fluridone may be applied. For example, in one embodiment, the applying step may be performed to apply fluridone at a rate of about 0.05 pounds fluridone per acre to about 0.5 pounds fluridone per acre. In other embodiments, fluridone may be applied at a rate of about 0.1 pounds fluridone per acre to about 0.5 pounds of fluridone per acre, about 0.2 pounds of fluridone per acre to about 0.4 pounds of fluridone per acre, about 0.225 pounds fluridone per acre to about 0.35 pounds fluridone per acre. In still other embodiments, fluridone may be applied at a rate of about 0.2 to about 0.8 pounds of fluridone per acre. Additionally or alternatively, the fluridone can be applied in such an amount that fluridone residues will remain in the soil for at least 1 month after application and/or in such an amount that effective weed control from the fluridone application is maintained for at least 1 month after the application.

When a second or additional herbicidal active ingredient is utilized in methods and compositions of the present disclosure, such active ingredient may be applied at a rate of greater than about 0.05 pounds active ingredient per acre, between about 0.05 pounds active ingredient per acre to about 0.5 pounds active ingredient per acre, and/or between about 0.1 pounds active ingredient per acre to about 0.4 pounds of active ingredient per acre.

Methods and compositions of this disclosure may be used, for example, in other permanent and/or seasonal crops in addition to cotton and soybeans. For example, the methods and compositions of the present disclosure may be utilized for weed control of crops including, but not limited to, trees, nuts, and/or vine crops. In other embodiments, methods and compositions of the present disclosure may be utilized for weed control of crops including, but not limited to, almond, pecan, pistachio, walnut, apple, pear, apricot, cherry, nectarine, peach, plum, prune, avocado, citrus, date, fig, grape, kiwi, olive, peanut, pomegranate, potato, sweet potato, pome, stone fruit, and/or tobacco crops.

In some embodiments, when methods and compositions of the present disclosure are used to control weeds in permanent crops, the herbicidal compositions will be applied to the soil where the permanent crops reside. This places the herbicide in proximity to the weeds which may be diverting nutrients and water in the soil from the crops. In such applications, the herbicidal compositions can be applied by any suitable means, including for example spraying liquid formulations of the herbicide(s) onto the soil (such as, but not limited to, from a backpack sprayer or another mobile spray apparatus or motorized vehicle with a tank containing the composition to be sprayed and that is moved through the subject area of soil to be treated, e.g., orchard, etc.) and/or by spreading solid herbicidal compositions on the soil. The application of the herbicidal composition can be conducted in the late fall and/or early spring and/or may be applied prior to emergence of weeds and/or subsequent to emergence of weeds (postemergence). The timing of application of the herbicidal composition may also be considered in relation to the annual growth cycle of the crop plant. For example, permanent crop plants generally have a dormant phase, a budding phase, a flowering phase, a fruit fill phase, and a harvest phase. In certain embodiments, the herbicidal composition is applied after the harvest phase of a given annual growth cycle and prior to the budding phase, or prior to the flowering phase, of the subsequent annual growth cycle. In some embodiments, only a single application of the herbicidal composition is made prior to the annual growing season of the permanent crop plant (which herein means the period from the budding phase to the harvest of the fruit, nut or other permanent crop), where that growing season is greater than about 90 days, greater than about 120 days, or greater than about 150 days. Such a single application of fluridone as a preemergent herbicide can, in certain embodiments, provide control of weeds for at least 50%, at least 75%, or 100%, of the growing season, and/or for at least 90 days, at least 120 days, and/or at least 150 days.

Methods and compositions of this disclosure may be used, for example, in the complete or partial control of noxious plants, also called weeds. In certain aspects, these noxious plants include, for example: Abutilon theophrasti, Acanthospermum hispidum, Acalypha ostryifolia, Amaranthus albus, Amaranthus hybridus, Amaranthus palmeri, Amaranthus retroflexus, Amaranthus rudis (waterhemp), Amaranthus spp., Amaranthus spinosus, Amaranthus tuberculatus, Ambrosia artemisiifolia, Ambrosia trifida, Acalypha ostryifolia, Anoda cristata, Artemisia biennis, barnyardgrass, Brachiaria platyphylla, Brassica kaber, Brassica napus, Bromus secalinus, Bromus tectorum, Calandrinia ciliate, Capsella bursa-pastoris, Cassia occidentalis, Cerastium vulgatum, Chenopodium album, Conyza spp., Conyza canadensis, Convolvulus arvensis, crabgrass, Croton glandulosus, Cucumis melo, Cyperus iria, Datura stramonium, Descurainia sophia, Descurainia pinnata, Desmodium tortuosum, Digitaria sanguinalis, Digitaria ischaemum, Eclipta prostrate, Echinochloa crus-galli, Eleusine indica, Eragrostis diffusa, Erigeron spp., Erodium cicutarium, Erodium moschatum, Euphorbia maculate, Euphorbia heterophylla, fleabane, fiddleneck, Geranium carolinianum, henbit, Hibiscus trionum, horseweed, Indigofera hirsute, Ipomoea coccinea, Ipomoea hederacea, Ipomoea lacunose, Ipomoea purpurea, Jacquemontia tamnifolia, Kochia scoparia, Lactuca serriola, lambsquarters, Lamium amplexicaule, Laminum purpureum, Lolium multiflorum, Malva neglecta, Malva parviflora, marestail, Matricaria maritime, Melochia corchorifolia, Mollugo verticillata, nutsedge, Oenothera laciniata, Panicum dichotomiflorum, Panicum texanum, Panicum maximus, Panicum maximum, pigweed, Plantago major, Poa annua, Polygonum convolvulus, Polygonum lapathifolium, Polygonum pensylvanicum, Polygonum persicaria, Portulaca oleracea, prickly lettuce, primrose, purslane, Raphanus raphanistrum, Richardia scabra, Salsola iberica, Senicio glabellus, Senicio vulgaris, Senna obtusifolia, Sesbania exaltata, Setaria faberi, Setaria glauca, Setaria verticillata, Setaria viridis, Sida spinosa, Silene latifolie, Sisymbrium altissimum, Solanum nigrum, Solanum ptycanthum, Solanum sarrachoides, Sonchus oleraceus, Sorghum halepense, Spurge spp., Stellaria media, swine cress, Taraxacum officinale, Trianthema portulacastrum, Tribulus terrestris, Tripleurospermum maritima, Verbesina encelioides, witchgrass, Xanthium strumarium, Hairy fleabane (Conyza bonariensis), Marestail (Conyza canadensis), Jungle rice (Echinochloa colona), Kochia (Kochia scoparia), Italian ryegrass (Lolium perenne spp. multiflorum), Ridge rygrass (Lolium rigidum), spiny amaranth (Amaranthus spinosus), Tall waterhelp (Amarantus spinosus), Tall waterhelp, (Amaranthus tuberculatus), Common ragweed (Ambrosia artemisiifolia), Giant ragweed (Ambrosia trifida), Goosegrass (Eleusine indica), Ragweed parthenium (Parthenium hysterophorus), Annual bluegrass (Poa annua), Johnsongrass (Sorghum halepense). In certain aspects, these or other weeds to be controlled can be resistant to glyphosate or other herbicides.

Any herbicide herein can be applied separately in a liquid or solid form, or a combination product containing some or all herbicides can be applied in either liquid or solid form. Typical liquid formulations include emulsions, suspensions (including suspensions containing microcapsules), solutions, emulsifiable concentrates, and flowables. Common solid forms include granules, wettable powders, water-dispersible solids (including water-dispersible granules containing microencapsulated herbicides) or dusts. The herbicidal formulations can also contain, in addition to the active herbicide(s) other ingredients such as adjuvants, surfactants, solvents, wetting agents, suspending agents, anti-caking agents, dispersing agents, emulsifiers, anti-freeze agents, antifoaming agents, and other additives.

Compositions according to this invention may contain the two or more herbicides in numerous different physical forms. In some cases, a composition may be produced by simply physically mixing (“tank mixing”) commercially available products containing the active herbicides. Alternatively, a package may be manufactured and sold which contains the two or more herbicides in separate containers, but packaged together, e.g. in a “multi-pack” format such as a “twin-pack” or “tri-pack”.

Alternatively, previously prepared compositions (“premixes”) containing the two or more herbicides can be produced. Suitable liquid compositions would include solutions or emulsions containing the two or more herbicides. A solid product containing the two or more herbicides could also be produced, for instance, as impregnated granules or flowable powders. The concentration of the active ingredient or ingredients in the herbicidal compositions of this invention is generally from about 0.001 to about 98 percent by weight. Concentrations from about 0.01 to about 90 percent by weight are often employed. In compositions designed to be employed as concentrates, the active ingredient is generally present in a concentration from about 5 to about 98 weight percent, preferably about 10 to about 90 weight percent. Such compositions are typically diluted with an inert carrier, such as water, before application. The diluted compositions usually applied to weeds or the location of weeds can contain about 0.0001 to about 1 weight percent active ingredient, or about 0.001 to about 0.05 weight percent.

In certain embodiments, a concentrated liquid composition comprising fluridone is used to prepare, upon dilution, a liquid composition for application to control weeds, including for application to the soil to control weeds in permanent crops as discussed herein. In some embodiments, such a concentrated liquid composition may have a fluridone concentration of at least about 0.5 pounds of fluridone per gallon (e.g., greater than or equal to 0.5 pounds fluridone per gallon), or at least about 1 pound of fluridone per gallon (e.g., greater than or equal to 0.5 pounds fluridone per gallon), and typically in the range of about 0.5 to 5 pounds of fluridone per gallon. In certain preferred embodiments, a concentrated solution of fluridone comprises 1.6 pounds fluridone per gallon of composition or 0.5 pounds fluridone per gallon of composition.

Prior to application, such as but not limited to a concentrated composition comprising an active ingredient such as fluridone may be diluted with another liquid, such as water, to prepare a less-concentrated composition. In certain embodiments, the volume ratio of the concentrate composition to the other liquid used in preparing the diluted composition for application is in the range of about 1:2 (v/v)(about 0.8 pounds active ingredient per gallon (w/v)) to about 1:300 (v/v)(about 0.005 pounds active ingredient per gallon (w/v)), or in the range of about 1:10 (v/v)(about 0.16 pounds active ingredient per gallon) to about 1:200 (about 0.008 pounds active ingredient per gallon(w/v)), or in the range of about 1:10 (v/v)(about 0.16 pounds active ingredient per gallon(w/v)) to about 1:100 (v/v)(about 0.016 pounds active ingredient per gallon(w/v)). Additionally or alternatively, the concentration of fluridone in the prepared liquid composition to be applied can be in the range of about 0.001 to about 1 pounds per gallon, more preferably about 0.016 to about 0.16 pounds per gallon. The application of the diluted composition to control weeds in permanent or other crops as disclosed herein can be achieved by any suitable method, with spray application being preferred (such as, but not limited to a backpack sprayer).

Typically, herbicidal compositions of the present disclosure will not be formulated for extended release and thus will be immediately bioavailable upon application to the soil, although, in certain embodiments they may be formulated for extended release. When herbicidal compositions of the present disclosure are not formulated for extended release, typically these formulations will not comprise extended release polymeric encapsulation, or other mechanisms to retard release of a herbicide.

Suitable agricultural adjuvants and carriers that may be useful in preparing the herbicidal mixtures or compositions of the invention are well known to those skilled in the art. Liquid carriers that can be used include water, toluene, xylene, petroleum naphtha, crop oil, acetone, methyl ethyl ketone, cyclohexanone, trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate, butyl acetate, propylene glycol monomethyl ether and diethylene glycol monomethyl ether, methanol, ethanol, isopropanol, amyl alcohol, ethylene glycol, propylene glycol, glycerine, and the like. Water is generally the carrier of choice for the dilution of concentrates. Solid carriers that can be used include talc, pyrophyllite clay, silica, attapulgus clay, kaolin clay, kieselguhr, chalk, diatomaceous earth, lime, calcium carbonate, bentonite clay, Fuller's earth, cottonseed hulls, wheat flour, soybean flour, pumice, wood flour, walnut shell flour, lignin, and the like.

It is usually desirable to incorporate one or more surface-active agents into the compositions of the present invention. Such surface-active agents are advantageously employed in both solid and liquid compositions, especially those designed to be diluted with carrier before application. The surface-active agents can be anionic, cationic or nonionic in character and can be employed as emulsifying agents, wetting agents, suspending agents, or for other purposes. Typical surface-active agents include salts of alkyl sulfates, such as diethanolammonium lauryl sulfate; alkylarylsulfonate salts, such as calciumdodecylbenzenesulfonate; alkylphenol-alkylene oxide addition products, such as nonylphenol-C₁₈ ethoxylate; alcohol-alkylene oxide addition products, such as tridecyl alcohol-C₁₆ ethoxylate; soaps, such as sodium stearate; alkylnaphthalenesulfonate salts, such as sodium dibutylnaphthalenesulfonate; dialkyl esters of sulfosuccinate salts, such as sodium di(2-ethylhexyl)-sulfosuccinate; sorbitol esters, such as sorbitol oleate; quaternary amines, such as lauryl trimethylammonium chloride; polyethylene glycol esters of fatty acids, such as polyethylene glycol stearate; block copolymers of ethylene oxide and propylene oxide; and salts of mono and dialkyl phosphate esters.

Other adjuvants commonly used in agricultural compositions include compatibilizing agents, antifoam agents, sequestering agents, neutralizing agents and buffers, corrosion inhibitors, dyes, odorants, spreading agents, penetration aids, sticking agents, dispersing agents, thickening agents, freezing point depressants, antimicrobial agents, and the like. The compositions may also contain other compatible components, for example, other herbicides, plant growth regulators, fungicides, insecticides, and the like and can be formulated with liquid fertilizers or solid, particulate fertilizer carriers such as ammonium nitrate, urea and the like.

As disclosed above, in certain aspects, methods are provided for controlling weeds in permanent crop plants. Permanent crop trials were conducted in California to evaluate crop safety and efficacy of fluridone in irrigated environments. Fluridone applied prior to emergence of weeds (“PRE”) at rates from about 0.1 pounds per acre (lb/ac) to about 0.8 lb/ac did not result in phytotoxicity of grape or orange and only in the highest application rate was phytotoxicity observed and only in minor amounts. In certain preferred embodiments, application of fluridone as a PRE herbicide delivers about 0.2 to about 0.4 lb fluridone/acre. These permanent crops appear to be tolerant of fluridone when applied as a PRE herbicide in amounts that provide prolonged weed control under permanent crop irrigation conditions.

Weed control results suggest fluridone applied PRE at about 0.2 pounds per acre, about 0.4 pounds per acre, and about 0.8 pounds per acre (lb/ac) provided acceptable control of various grass, sedge, and broadleaf weed species across a five to seven month period. Surprisingly, there is potential for use of fluridone—which is typically used in aqueous environments—as an effective, long-term PRE herbicide in irrigated permanent crops. In some embodiments of the present disclosure, fluridone can be used with one or more additional herbicides in permanent crops, which may be watered by irrigation.

Irrigation in permanent crop and other crop applications herein can be achieved by any suitable method. For example, low-flow irrigation, high-flow irrigation, surface-irrigation, subsurface-irrigation may be used. In certain embodiments, irrigation may be achieved by spray irrigation, microspray irrigation, furrow, fixed spray irrigation, drip irrigation, rotor irrigation, impact irrigation, bubbler irrigation, canals, soaker hoses, micro-sprinkler, and/or any other method of irrigation that provides water to a crop to be irrigated.

The quantity of applied irrigation water may vary with the crop involved, the growing conditions in the region in which the crop is growing, the amount of rainfall experienced, and other factors. In permanent crop applications herein, irrigation is commonly applied to ensure that at least a given quantity of water per day and/or per week, on average, is delivered to the soil in which the crop resides (through the irrigation and, if any, rain) during a growing season of the crop plant. In certain forms, such given quantity of water is an average of at least about 0.1 inches (about 0.25 cm) of water per day, or an average of about 0.2 inches (about 0.51 cm) of water per day, or an average of at least about 0.3 inches (about 0.76) of water per day, and typically this average is in the range of about 0.05 (about 0.127 cm) to about 0.5 inches (about 1.27 cm) of water per day. In some embodiments, irrigation is conducted as needed to ensure that the soil receives some quantity of water (usually at least 0.001 inches, at least 0.01 inches, and/or at least 0.1 of water through irrigation, rainfall, or otherwise) at least once every week, once every ten days, once every two weeks, and/or once every three weeks, and/or such that during the growing season (or during a period of control of at least 60 days, at least 90 days, at least 120 days, or at least 150 days), the soil does not experience any period of greater than a week, ten days, two weeks, and/or three weeks during which the soil fails to receive such a quantity of water. The duration of the growing season during which irrigation is applied may vary with the particular crop plant and conditions at hand, but in certain embodiments such duration is at least about 60 days, at least about 90 days, at least about 120 days, or at least about 150 days, and typically in the range of about 120 days to about 240 days. Illustratively, in many permanent crop plants grown in the United States, such is citrus trees and nut trees, it is common to begin irrigation in March or April and to continue irrigation until October or November, when harvest of the citrus fruit or nuts occurs.

It will be understood that while average per day delivery of water to soil is discussed above, it is common to deliver water to the soil at intervals other than daily, for example weekly bi-weekly, and/or once every three weeks. Generally, irrigation is applied every 1 to 3 weeks to achieve the desired average irrigation amounts, which may be crop specific (for example, but not limited to, grapes may require more water than almonds). Recitation of averages above intends inclusion of such other delivery intervals, so long as they deliver the per-day averages specified. As well, it will be understood that applied water levels may vary during various periods of the growing season, for example with more water being applied during hotter months to account for evaporative losses and other factors, and less water being applied during cooler months. Again, recitation of averages above intends inclusion of such variations over time, so long as they deliver the per-day averages specified. As well, as commonly used and understood in the art, the recitation of delivered quantities of water (by irrigation and/or rainfall) in inches or fractions thereof refers to the volume of water needed to cover a given water-impenetrable surface area to a depth of the value given.

When drip irrigation is used, the quantity of water used or needed by plants is often calculated by the maximum daily potential evapotranspiration (ET). Maximum daily potential evapotranspiration or gallons of water needed per plant may be calculated by the equation:

$\begin{matrix} {{{Gallons}\mspace{14mu}{per}\mspace{14mu}{plant}} = \frac{\begin{matrix} {0.623*{Plant}\mspace{14mu}{Area}*} \\ {{Plant}\mspace{14mu}{Factor}*{Potential}\mspace{14mu}{ET}} \end{matrix}}{{Drip}\mspace{14mu}{system}\mspace{14mu}{efficiency}}} & \left( {{Equation}\mspace{14mu} 1} \right) \end{matrix}$ 0.623 is a conversion factor representing the gallons of water applied when one square foot of ground is irrigated with one inch of water. The Plant area is measured in square feet. The Plant Factor is a correction factor for how different plants use water under the same conditions. 1.00 may be used for ground cover, flower beds, evergreens, perennials, small shrubs, and/or vines; 0.85 may be used for apple trees, cherry trees, and/or walnut trees; 0.80 may be used for mature shade trees; 0.75 may be used for pecans, peaches, plums, pears, apricots, and/or almonds; 0.70 may be used for ornamental plants, and/or large shrubs; 0.40 may be used for established low-water or native or low water use plants. Typical efficiency values are about 85% (about 0.85) to about 90% (about 0.9). The potential evapotranspiration varies based upon soil types. These and other similar considerations can be taken into account when carrying out methods in accordance with the present disclosure.

In order to promote a further understanding of the present invention and its various embodiments, the following specific examples are provided. It will be understood that these examples are illustrative and not limiting of the invention.

Example 1 Greenhouse and Field Efficacy Against Palmer Amaranth and Crop Safety

Materials and Methods:

Field and greenhouse trials were conducted to determine the efficacy and extent of safening of fluridone on fomesafen and flumioxazin.

Cotton was planted in fields in May. The field was then over seeded with P. amaranth. On the same day, pre-emergent herbicides were applied at the rates of (1) 0.2 lb/A fluridone; (2) 0.25 lb/A fomesafen; and (3) a combination of 0.2 lb/A fluridone and 0.25 lb/A fomesafen. Within 24 hours of application of the herbicide, 0.25 inches of rain was recorded. An additional planting of cotton, by hand, was conducted in August with multiple rates.

In addition to these field trials, greenhouse studies were also undertaken. The greenhouse studies evaluated the use of fluridone, fomesafen, and the combination of fluridone and fomesafen as well as the affect of soil types, and moisture conditions. Four soil types were examined: a predominantly clay soil, a sandy loam soil, a loamy peat soil, and a sandy soil. The moisture conditions evaluated were at 0.2 inches of water, and 1.5 inches of water.

Results:

All the treatments in the May planting displayed significant control of P. amaranth and other weeds compared to the untreated control, however there was no significant difference between the treatments at various concentrations. The weather conditions observed during this trial were ideal for both cotton growth and optimal herbicide efficacy.

In the August planting, the various concentrations of herbicides were tested for phytotoxicity to emerging cotton in a sandy loam soil. Only at the ratio of 0.4 lbs/A of fluridone to 0.4 lbs/A of fomesafen was any phytotoxicity seen, and the phytotoxicity observed at this ratio was minimal. The weather conditions observed during this trial were ideal for both cotton growth and optimal herbicide efficacy. Table 1 describes the conditions used during the greenhouse trials.

TABLE 1 Rates used in greenhouse trial examining cotton response across soil types and 2 moisture conditions. Product went out at ratios listed and cotton was examined for phytotoxicity. Fomesafen treatments at a rate of 0.15 lb/A and above exhibited stunting to the cotyledon and first 3 true leaves. Herbicide Ratio of solution Fluridone concentration Application Rate to Plot Number Herbicide (lb/gal) (lb/A) fomesafen 1 n/a n/a n/a n/a 2 fluridone 2 0.1 1:0 3 fluridone 2 0.15 1:0 4 fluridone 2 0.175 1:0 5 fluridone 2 0.2 1:0 6 fluridone/ 2 0.1 1:0.625 fomesafen 7 fluridone/ 2 0.15 1:0.625 fomesafen 8 fluridone/ 2 0.175 1:0.625 fomesafen 9 fluridone/ 2 0.2 1:0.625 fomesafen 10 fomesafen 2 0.1 0:1 11 fomesafen 2 0.15 0:1 12 fomesafen 2 0.175 0:1 13 fomesafen 2 0.2 0:1

There was some variation in weed control which depended on the soil types. For example, under low moisture conditions across some soil types, fomesafen alone was not able to provide complete P. amaranth control. Additionally, some stunting was observed in the fomesafen treatments as compared to the fluridone and fluridone/fomesafen combination of treatments, which indicates that the fluridone is able to safen fomesafen under less than ideal growing conditions. Under ideal growing conditions in the greenhouse, all herbicidal applications worked similarly in that no phytotoxicity was observed in the various soil types. However there was some variation in weed control which depended on the soil types. For example, under low moisture conditions across some soil types, fomesafen alone was not able to provide complete P. Amaranth control. Additionally, some stunting was observed in the fomesafen treatments as compared to the fluridone and fluridone/fomesafen combination of treatments, which indicates that the fluridone is able to safe and fomesafen under less than ideal growing conditions.

FIG. 1 shows a digital image of the May planting field trials 1 week post treatment and 9 weeks post treatment. Brake is a formulation of fluridone. Brake F2™ is a formulation of fluridone and fomesafen. Fomesafen treatment is also shown. Each treatment showed control of P. amaranth and no phytotoxicity was observed in any treatment.

FIG. 2 shows a digital image of the August planting taken 7 weeks post treatment using an application ratio of 0.2 lbs/acre:0.2 lbs/acre fluridone:fomesafen and 0.4 lbs/acre:0.4 lbs/acre fluridone:fomesafen. P. amaranth was controlled in both treatment rates and minimal to no phytotoxicity was observed in either application rate. Table 2 summarizes the conditions used during the August field trials.

TABLE 2 Field rates applied of fluridone and fomesafen in August to cotton. Treatment was applied as a pre-emergent application. Amaranthus palmeri was overseeded onto the area. Plots were evaluated for any phytotoxicity to cotton and weed control was evaluated. Herbicide Ratio of solution to concentration Application Rate Fluridone Plot Number Herbicide (lb/gal) (lb/A) fomesafen 1 n/a n/a n/a n/a 2 Fluridone 2 0.2 1:0 3 Fomesafen 2 0.2 0:1 4 Fluridone 2 0.1 1:0.5 Fomesafen 2 0.05 5 Fluridone 2 0.1 1:0.75 Fomesafen 2 0.075 6 Fluridone 2 0.1 1:1 Fomesafen 2 0.1 7 Fluridone 2 0.15 1:0.8 Fomesafen 2 0.125 8 Fluridone 2 0.15 1:1 Fomesafen 2 0.15 9 Fluridone 2 0.15 1:1.7 Fomesafen 2 0.175 10 Fluridone 2 0.2 1:3.75 Fomesafen 2 0.75 11 Fluridone 2 0.2 1:0.75 Fomesafen 2 0.15 12 Fluridone 2 0.2 1:1 Fomesafen 2 0.2 13 Fluridone 2 0.4 1:1 Fomesafen 2 0.4

Example 2 Safening of Fluridone by Flumioxazin in Soybeans when Applied Pre-Plant

Materials and Methods:

A climate-regulated greenhouse trial was conducted to determine the efficacy and extent of safening of herbicidal compositions of fluridone and flumioxazin applied to soybeans.

In this trial, soybeans were treated with various herbicidal compositions. The quantity of fluridone applied was maintained constant at a rate of 0.2 lb/A and 0.1 lb/A fluridone and the quantity of flumioxazin was varied from 0.008 lb/A to 0.17 lb/A flumioxazin. One gallon pots with sandy loam soil were treated with a herbicidal composition, and three soybeans were planted in each pot 7 days after application of the herbicide (i.e., the herbicide was applied 7 days pre-plant) Three pots were prepared and treated for each herbicide composition. Approximately 0.15 inches of water was applied to each pot four hours after application. Irrigation was applied as the plants emerged through the soil 4 days after treatment (DAT) after the first visible signs of soil cracking due to plant emergence was observed. Irrigation comprised application of 0.5 inches of water for 2 days followed by 0.25 inches of water for 2 days, followed by 0.15 inches of water per day for the remainder of the trial. The greenhouse was maintained at 26±5° C. during the day and 11±1° C. during the night.

TABLE 3 Herbicidal compositions applied to soybean plants of EXAMPLE 2. EXAMPLE 2: Soybean Pre-plant using flumioxazin and fluridone. Pre-emergent and Pre Plant Applications of fluridone in combination with flumioxazin on Soybean Trial ID: 20140117.1 BH    Protocol ID: 20140117.1 BH Trt Treatment Form Form Form Des- Rate No. Name Conc Unit Type cription Rate Unit 1 Flumioxazin 51.00 % WG 7 Day 8 oz/a 2 Fluridone 2 LB/GAL EC 7 Day 0.05 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.255 lb ai/a 3 Fluridone 2 LB/GAL EC 7 Day 0.10 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.255 lb ai/a 4 Fluridone 2 LB/GAL EC 7 Day 0.20 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.255 lb ai/a 5 Fluridone 2 LB/GAL EC 7 Day 0.03 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.255 lb ai/a 6 Flumioxazin 51.00 % WG 7 Day 0.17 lb ai/a 7 Fluridone 2 LB/GAL EC 7 Day 0.05 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.17 lb ai/a 8 Fluridone 2 LB/GAL EC 7 Day 0.10 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.17 lb ai/a 9 Fluridone 2 LB/GAL EC 7 Day 0.20 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.17 lb ai/a 10 Fluridone 2 LB/GAL EC 7 Day 0.03 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.17 lb ai/a 11 Flumioxazin 51.00 % WG 7 Day 0.128 lb ai/a 12 Fluridone 2 LB/GAL EC 7 Day 0.05 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.128 lb ai/a 13 Fluridone 2 LB/GAL EC 7 Day 0.10 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.128 lb ai/a 14 Fluridone 2 LB/GAL EC 7 Day 0.20 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.128 lb ai/a 15 Fluridone 2 LB/GAL EC 7 Day 0.03 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.128 lb ai/a 16 Flumioxazin 51.00 % WG 7 Day 0.016 lb ai/a 17 Fluridone 2 LB/GAL EC 7 Day 0.10 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.016 lb ai/a 18 Fluridone 2 LB/GAL EC 7 Day 0.20 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.016 lb ai/a 19 Flumioxazin 51.00 % WG 7 Day 0.008 lb ai/a 20 Fluridone 2 LB/GAL EC 7 Day 0.10 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.008 lb ai/a 21 Fluridone 2 LB/GAL EC 7 Day 0.20 lb ai/a Flumioxazin 51.00 % WG 7 Day 0.008 lb ai/a 22 UTC 7 Day Results:

FIG. 6 shows a series of five digital images of soybeans planted during the trial. In the first image from the left, a herbicidal composition comprising 0.2 lb/A fluridone and 0.008 lb/A of flumioxazin was applied to the plant; in the second digital image 0.2 lb/A fluridone and 0.016 lb/A flumioxazin was applied; in the third digital image 0.2 lb/A fluridone and 0.128 lb/A flumioxazin was applied; in the fourth digital image, 0.2 lb/A fluridone and 0.17 lb/A flumioxazin was applied; in the fifth digital image, no herbicidal compositions were applied and used an untreated control.

FIG. 7 shows a graph of the percent chlorosis (PHYBLE) observed on the soybean plants of the present trial. The untreated control soybean plants exhibited 0% chlorosis. Soybeans treated with 0.2 lb/A fluridone in combination with the smallest rate of flumioxazin, 0.008 lb/A flumioxazin, exhibited 100% chlorosis and was fatal to the soybean plants. Chlorosis decreased as the rate of flumioxazin increased. Soybeans treated with 0.2 lb/A fluridone in combination with the largest rate of flumioxazin, 0.17 lb/A flumioxazin, exhibited 0% chlorosis. These data evidences that flumioxazin safens soybeans against the application of fluridone when applied pre-plant.

A similar trend is observed in FIG. 8. The untreated control soybean plants exhibited 0% chlorosis. Soybeans treated with 0.1 lb/A fluridone in combination with the smallest rate of flumioxazin, 0.008 lb/A flumioxazin, exhibited 48.3% chlorosis. Chlorosis generally decreased as the rate of flumioxazin increased. Soybeans treated with 0.1 lb/A fluridone in combination with the largest does of flumioxazin, 0.17 lb/A flumioxazin, exhibited only 3.3% chlorosis. These data also evidence that flumioxazin safens soybeans against the application of fluridone when applied pre-plant.

Example 3 Pre-Emergent Application of Combinations of Fluridone with Flumioxazin or Fomesafe in Cotton and Soybeans

A trial was conducted in a climate-controlled growth chamber to determine the efficacy and extent of safening of combinations of fluridone with flumioxazin or fluridone with fomesafen on soybeans and cotton.

0.1 L conical assay tubes were planted with a cotton or soybean seed in a sample of sandy loam soil. Seven tubes were prepared for each herbicide application rate. Application of a herbicide composition was performed after planting the seed and prior to the plant's emergence from the soil (i.e., pre-emergent or PRE). Approximately 0.15 inches of water was applied to each pot four hours after application. Irrigation was applied as the plants emerged through the soil 4 days after treatment (DAT) after the first visible signs of soil cracking due to plant emergence was observed. Irrigation comprised application of 0.5 inches of water for 2 days followed by 0.25 inches of water for 2 days, followed by 0.15 inches of water per day for the remainder of the trial. The greenhouse was maintained at 26±5° C. during the day and 11±1° C. during the night. Table 4 shows the herbicidal compositions applied to soybean plants of the present example.

TABLE 4 Herbicidal compositions applied to soybean plants of EXAMPLE 3. EXAMPLE 3: Pre-emergent Applications of Brake, Reflex, and Valor on Soybean to Evaluate Injury Under Cool and Moist Conditions Trial ID: 20140203.2    Protocol ID: 20140203.2 Trt Treatment Form Form Form Rate No. Name Conc Unit Type Rate Unit 1 Fluridone 2 LBA/GAL EC 0.025 lb ai/a 2 Fluridone 2 LBA/GAL EC 0.05 lb ai/a 3 Fluridone 2 LBA/GAL EC 0.1 lb ai/a 4 Fluridone 2 LBA/GAL EC 0.2 lb ai/a 5 Fomesafen 2 LBA/GAL EC 0.125 lb ai/a 6 Fomesafen 2 LBA/GAL EC 0.25 lb ai/a 7 Fomesafen 2 LBA/GAL EC 0.375 lb ai/a 8 Fomesafen 2 LBA/GAL EC 0.5 lb ai/a 9 Flumioxazin 51 % WG 1.5 oz/a 10 Flumioxazine 51 % WG 3 oz/a 11 Flumioxazine 51 % WG 6 oz/a 12 Flumioxazin 51 % WG 9 oz/a 13 Fluridone 2 LBA/GAL EC 0.025 lb ai/a Fomesafen 2 LBA/GAL EC 0.5 lb ai/a 14 Fluridone 2 LBA/GAL EC 0.05 lb ai/a Fomesafen 2 LBA/GAL EC 0.5 lb ai/a 15 Fluridone 2 LBA/GAL EC 0.1 lb ai/a Fomesafen 2 LBA/GAL EC 0.5 lb ai/a 16 Fluridone 2 LBA/GAL EC 0.1 lb ai/a Flumioxazin 51 % WG 1.5 oz/a 17 Fluridone 2 LBA/GAL EC 0.1 lb ai/a Flumioxazin 51 % WG 3 oz/a 18 UTC

Table 5 shows the herbicidal compositions applied to cotton plants of the present example.

TABLE 5 Herbicidal compositions applied to cotton plants of EXAMPLE 3. EXAMPLE 3: Pre-emergent Applications of Brake, Reflex, and Valor on Cotton to Evaluate Injury Under Cool and Moist Conditions Trial ID: 20140203.1    Protocol ID: 20140203.1 Trt Treatment Form Form Form Rate No. Name Conc Unit Type Rate Unit 1 Fluridone 2 LBA/GAL EC 0.05 lb ai/a 2 Fluridone 2 LBA/GAL EC 0.1 lb ai/a 3 Fluridone 2 LBA/GAL EC 0.2 lb ai/a 4 Fluridone 2 LBA/GAL EC 0.4 lb ai/a 5 Fomesafen 2 LBA/GAL EC 0.125 lb ai/a 6 Fomesafen 2 LBA/GAL EC 0.25 lb ai/a 7 Fomesafen 2 LBA/GAL EC 0.375 lb ai/a 8 Fomesafen 2 LBA/GAL EC 0.5 lb ai/a 9 Flumioxazin 51 % WG 0.0125 oz/a 10 Flumioxazin 51 % WG 0.025 oz/a 11 Flumioxazin 51 % WG 0.075 oz/a 12 Flumioxazin 51 % WG 0.1 oz/a 13 Fluridone 2 LBA/GAL EC 0.1 lb ai/a Fomesafen 2 LBA/GAL EC 0.25 lb ai/a 14 Fluridone 2 LBA/GAL EC 0.2 lb ai/a Fomesafen 2 LBA/GAL EC 0.25 lb ai/a 15 Fluridone 2 LBA/GAL EC 0.4 lb ai/a Fomesafen 2 LBA/GAL EC 0.25 lb ai/a 16 Fluridone 2 LBA/GAL EC 0.2 lb ai/a Flumioxazin 51 % WG 0.075 oz/a 17 Fluridone 2 LBA/GAL EC 0.4 lb ai/a Flumioxazin 51 % WG 0.075 oz/a 18 UTC Soybeans:

FIG. 9 shows the height of soybean plants 9 days after treatment with a herbicide compositions comprising fluridone; flumioxazin; and various ratios of fluridone and flumioxazin.

FIG. 10 shows the percentage of chlorosis observed in soybean plants treated with various herbicidal compositions. For example, when soybean plants were treated with fluridone, 80% chlorosis was observed. When a herbicidal composition comprising fluridone and flumioxazin was applied, the percentage chlorosis observed decreased. These data evidence that when fluridone and flumioxazin are used in combination, increasing rates of flumioxazin decreases the quantity of chlorosis observed on soybeans.

FIG. 11 shows the percentage of chlorosis observed in soybean plants treated with various herbicidal compositions. For example, when soybean plants were treated with fluridone and fomesafen a decrease in chlorosis was not observed in contrast to the decrease of chlorosis observed with fluridone and flumioxazin are used in combination.

These data evidence that when fluridone and flumioxazin are used in combination, a safening affect is observed on soybean plants as measured by percent chlorosis observed. When fluridone and fomesafen are used in combination a safening affect is not observed on soybean plants as measured by percent chlorosis observed.

Cotton:

FIG. 12 show digital images of cotton plants 16 days after treatment with herbicidal compositions comprising fluriodone and fomesafen. Generally speaking, the crop phytotoxicity and growth inhibition caused by fomesafen alone was improved by the use of a combination of fluridone and fomesafen. Starting from the left, the first plant is a cotton plant that was not treated with a herbicidal composition. The middle plant is a cotton plant treated with 0.25 lb/A of fomesafen. The plant on the right is a cotton plant treated with 0.25 lb/A of fomesafen in combination with fluridone.

FIG. 13 shows the height of cotton plants 16 days after treatment with a herbicidal composition. Shown are untreated control plants, plants treated with 0.25 lb/A fomesafen, and plants treated with a combination of 0.1 lb/A fluridone and 0.25 lb/A fomesafen.

FIG. 14 shows the height of cotton plants 29 days after treatment with a herbicidal composition. Shown are untreated control plants, plants treated with 0.25 lb/A fomesafen, and plants treated with a combination of 0.1 lb/A fluridone and 0.25 lb/A fomesafen. These data evidence that cotton plants treated with a combination of fluridone and fomesafen exhibit less phytotoxicity and growth inhibition than plants treated only with fluridone. FIG. 15 shows the height of cotton plants treated with various rates of flumioxazin. As can be seen from the bar graph, as the rate of flumioxazin is increased, the height of cotton plants decrease. At the highest rates, flumioxazin was fatal to cotton plants. At application rates greater than 0.025 lb/A flumioxazin, cotton plants were significantly injured.

FIG. 16 shows digital images of cotton plants treated with flumioxazin. As the rate of flumioxazin increases, the height of the cotton plants decreases.

FIG. 17 shows the crop stand, which is the number of viable plants, for cotton plants treated with 0.5 lb/A flumioxazin, 0.2 lb/A fluridone plus 0.05 lb/A flumioxazin, as well as plants that went untreated as a control. The crop stand was one surviving plants out of seven for cotton plants treated with 0.05 lb/A flumioxazin. The crop stand was four surviving plants out of seven cotton plants treated with 0.2 lb/A fluridone.

FIG. 18 shows a digital image where cotton plants were various treatments were applied to cotton plants. One set of cotton plants were treated with flumioxazin at the rate of 0.05 lb/A, one set of plants was treated with a combination of flumioxazin at 0.05 lb/A and fluridone at 0.2 lb/A, and one set was left untreated as an untreated control (UTC).

FIG. 19 shows the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury measured 26 days after treatment. As shown here, when flumioxazin is used alone at the rate of 0.05 lb/A all of the cotyledons show brown spotting. When fluridone is added at the rate of 0.2 lb/A or 0.4 lb/A, the number of cotyledons that have brown spots decreases by 75%.

FIG. 20 shows the growth stage of cotton plants 26 days after treatment. Growth stage is measured using the following scale:

0=non-emerged plant

1=emerged plant with open cotyledons

2=first true leaf stage

3=second true leaf stage

As can be seen in the graph, cotton plants treated with flumioxazin at the rate of 0.05 lb/A experience the most growth stunting as compared to the untreated control plants. Growth stunting decreases as the rate of fluridone increases when used in combination with flumioxazin.

When evaluated, these data evidence that the chlorosis caused by fluridone decreased as the rate of flumioxazin increased in soybeans. It was also observed that fomesafen did not decrease the chlorosis caused by fluridone in soybean plants. In cotton, the phytotoxicity and growth inhibition caused by fomesafen was improved by the addition of fluridone to fomesafen. In cotton, the use of flumioxazin in combination with fluridone decreased crop injury as compared to when flumioxazin is used by itself.

Example 4 Pre-Emergent Application of Combinations of Fluridone with Flumioxazin or Fomesafe in Cotton and Soybeans

The trial of EXAMPLE 3 was repeated using 21 replicated samples for each herbicidal application instead of 7 for each herbicidal application.

Table 6 shows the herbicide compositions applied to soybean plants of EXAMPLE 4.

TABLE 6 Herbicide compositions applied to pre-emergent soybean plants. EXAMPLE 4: Soybean Pre-emergent Applications of fluridone, fomesafen, and flumioxazin on Soybean to Evaluate Injury Under Cool and Moist Conditions Trial ID: 20140304     Protocol ID: 20140304.2 Trt Treatment Form Form Form Rate Appl Appl No. Type Name Conc Unit Type Rate Unit Code Description 1 CHK UTC A Pre- Emergent 2 HERB Fluridone 2 LBA/GAL EC 0.075 LBAI/A A Pre- Emergent 3 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent 4 HERB Fluridone 2 LBA/GAL EC 0.15 LBAI/A A Pre- Emergent 5 HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre- Emergent 6 HERB Flumioxazin 51 % WG 0.1 LBAI/A A Pre- Emergent 7 HERB Flumioxazin 51 % WG 0.15 LBAI/A A Pre- Emergent 8 HERB Fluridone 2 LBA/GAL EC 0.075 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre- Emergent 9 HERB Fluridone 2 LBA/GAL EC 0.075 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.1 LBAI/A A Pre- Emergent 10 HERB Fluridone 2 LBA/GAL EC 0.075 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.15 LBAI/A A Pre- Emergent 11 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre- Emergent 12 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.1 LBAI/A A Pre- Emergent 13 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.15 LBAI/A A Pre- Emergent 14 HERB Fluridone 2 LBA/GAL EC 0.15 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre- Emergent 15 HERB Fluridone 2 LBA/GAL EC 0.15 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.1 LBAI/A A Pre- Emergent 16 HERB Fluridone 2 LBA/GAL EC 0.15 LBAI/A A Pre- Emergent HERB Flumioxazin 51 % WG 0.15 LBAI/A A Pre- Emergent 17 HERB Fomesafen 2 LBA/GAL EC 0.5 LBAI/A A Pre- Emergent 18 HERB Fomesafen 2 LBA/GAL EC 1 LBAI/A A Pre- Emergent 19 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent HERB Fomesafen 2 LBA/GAL EC 0.5 LBAI/A A Pre- Emergent 20 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre- Emergent HERB Fomesafen 2 LBA/GAL EC 1 LBAI/A A Pre- Emergent

Table 7 shows the herbicide compositions applied to cotton plants of EXAMPLE 4.

TABLE 7 Herbicide compositions applied to pre-emergent cotton plants .EXAMPLE 4: Cotton Pre-emergent Applications of fluridone, fomesafen, and flumioxazin on Cotton to Evaluate Injury Under Cool and Moist Conditions Trt Treatment Form Form Form Rate Appl Appl No. Type Name Conc Unit Type Rate Unit Code Description 1 CHK UTC A Pre-Emergent 2 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent 3 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent 4 HERB Flumioxazin 51 % WG 0.025 LBAI/A A Pre-Emergent 5 HERB Flumioxazin 51 % WG 0.033 LBAI/A A Pre-Emergent 6 HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre-Emergent 7 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.025 LBAI/A A Pre-Emergent 8 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.033 LBAI/A A Pre-Emergent 9 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre-Emergent 10 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.025 LBAI/A A Pre-Emergent 11 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.033 LBAI/A A Pre-Emergent 12 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Flumioxazin 51 % WG 0.05 LBAI/A A Pre-Emergent 13 HERB Fomesafen 2 LBA/GAL EC 0.125 LBAI/A A Pre-Emergent 14 HERB Fomesafen 2 LBA/GAL EC 0.25 LBAI/A A Pre-Emergent 15 HERB Fomesafen 2 LBA/GAL EC 0.375 LBAI/A A Pre-Emergent 16 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.125 LBAI/A A Pre-Emergent 17 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.25 LBAI/A A Pre-Emergent 18 HERB Fluridone 2 LBA/GAL EC 0.1 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.375 LBAI/A A Pre-Emergent 19 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.125 LBAI/A A Pre-Emergent 20 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.25 LBAI/A A Pre-Emergent 21 HERB Fluridone 2 LBA/GAL EC 0.2 LBAI/A A Pre-Emergent HERB Fomesafen 2 LBA/GAL EC 0.375 LBAI/A A Pre-Emergent Soybeans:

FIG. 24 shows the percent chlorosis observed 21 days after treatment of soybean plants with various herbicidal compositions. A decrease in chlorosis is observed as the rate of flumioxazin is increased when used with fluridone.

FIG. 25 shows a series of digital images of soybean plants treated with various herbicide compositions including 0.1 lb/A fluridone; 0.1 lb/A fluridone and 0.05 lb/A flumioxazin; 0.1 lb/A fluridone and 0.1 lb/A flumioxazin; and 0.1 lb/A fluridone and 0.15 lb/A flumioxazin.

These data evidence that in soybean plants, flumioxazin safens fluridone by decreasing the chlorosis observed.

Cotton:

FIG. 21 and FIG. 22 show the damage to cotton plants 16 days after treatment and 21 days after treatment with various herbicidal compositions as measured by the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury. These data evidence that fluridone is safening fomesafen as the damage observed decreases when the application rate of fomesafen is increased when used in conjunction with fluridone.

FIG. 23 shows a series of three digital images of cotton plants treated with fomesafen alone, fomesafen applied with fluridone, and an untreated control group.

These data evidence that in cotton plants, fluridone safens fomesafen by reducing the injury to plants observed as the number of cotyledons with excessive wrinkling or brown spotting and that fluridone safens flumioxazin by reducing the injury to plants observed as the number of cotyledons with excessive wrinkling or brown spotting.

Example 5 Pre-Emergent Application of Combinations of Fluridone with Flumioxazin in Corn

Materials and Methods:

A greenhouse trial was conducted to determine if fluridone and flumioxazin have a safening effect on the other when applied to corn plants prior to emergence from the soil. Ten compositions were applied to corn plants after corn seed had been planted, but prior to the corn plants emergence from the soil, and each application was repeated seven times. The herbicidal compositions applied are described in Table 8, where there is an untreated control (Application No. 1), fluridone applied alone (Applications Nos. 5-7), flumioxazin applied alone (Application Nos. 2-4), and combinations of fluridone and flumioxazin (Application Nos. 8-10).

TABLE 8 Applications of herbicidal compositions to corn plants applied pre-emergent to the plants. Application Rate Fluridone Rate Flumioxazin No. Applied Applied Units 1 0 0 lb/A 2 0 0.05 lb/A 3 0 0.1 lb/A 4 0 0.15 lb/A 5 0.05 0 lb/A 6 0.1 0 lb/A 7 0.15 0 lb/A 8 0.05 0.05 lb/A 9 0.1 0.1 lb/A 10 0.15 0.15 lb/A Results:

FIG. 26 shows the percentage of leaves with visible bleaching injury measured 12 days after application (% PHYBLE) when various herbicidal compositions are applied to corn plants. As can be seen from this bar graph, the percentage of leaves with visible bleaching damage, a measure of chlorosis, decreases when a combination of fluridone and flumioxazin is used as compared to when fluridone is used alone. These data evidence that flumioxazin is safening fluridone on cotton plants as measured by the percentage of leaves with visible bleaching injury.

FIG. 27 shows a digital image of corn plants when various herbicidal compositions are applied. The image was taken 12 days after treatment.

FIG. 28 shows the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury observed on cotton plants when various herbicidal compositions are applied (% PHYGEN) measured 12 days after application. These data show, in particular, that when fluridone is applied at a rate of 0.1 lb/A and flumioxazin is applied at the rate of 0.1 lb/A the percentage of cotyledons with excessive wrinkling and brown spotting due to herbicide injury is decreased as compared to when flumioxazin is applied alone.

FIG. 29 shows digital images of corn plants when various herbicidal compositions are applied. The image was captured 12 days after treatment.

Example 6 Crop Safety and Weed Control in Almond

Materials and Methods:

Field trials were conducted in California to determine sweet almond (Prunus dulcis) tolerance to fluridone and efficacy of fluridone in an irrigated orchard environment. Trial locations included a two-year old almond stand in Kerman, Calif. and a six-year old stand in Shafter, Calif. The soil in both locations is classified as a sandy loam. Applications prior to emergence of weeds (PRE) of herbicides were made in the month of January in Kerman and in the month of January in Shafter. Herbicide treatments in both locations included fluridone applied at 0.1 lb/ac (about 11.25 kg/km²), 0.2 lb/ac (about 22.5 kg/km²), 0.4 lb/ac (about 45 kg/km²), and 0.8 lb/ac (about 90 kg/km²) and flumioxazin at 0.38 lb/ac (about 42.75 kg/km²)(Table 9). Rainfall (0.32 in (about 0.813 cm)) and irrigation (1.5 in (about 3.81 cm)) one day after PRE applications were used to incorporate herbicides into the soil at the Kerman and Shafter locations, respectively. Both sites were irrigated as needed during the growing season to avoid drought conditions. Visual evaluations of crop injury and weed control were made monthly on a 0 to 100% scale. Postemergent (POST) broadcast applications of a non-selective, contact herbicide was broadcast across all treatments in Kerman prior to the 90 days after treatment and 119 days after treatment (DAT) ratings. Thus, data from those ratings dates was not evaluated. No POST applications were made in Shafter.

Results:

The data from both locations suggest that almond is tolerant to PRE applications of fluridone and flumioxazin. The greatest phytotoxicity (8.3%) was observed in Shafter 158 and 180 DAT in areas treated with 0.8 lb fluridone/ac. Phytotoxicity was not observed following any PRE herbicide application in Kerman.

Weed control provided by PRE applications of fluridone was effective in both locations across the trial period. In Kerman, fluridone applied at 0.4 lb/ac (about 45 kg/km²) and 0.8 lb/ac (about 90 kg/km²) provided greater control than other fluridone rates but not it was not significantly different than flumioxazin at any rating date. Evaluations 184 DAT suggest 0.4 and 0.8 lb fluridone/ac provided 10 percent greater crabgrass control (Digitaria spp.) and similar yellow nutsedge (Cyperus esculentus L.) control to flumioxazin (FIG. 30). However, hairy fleabane (Conyza bonariensis) control was 20 to 33 percent less than flumioxazin.

The yellow nutsedge and hairy fleabane results provided different results. Those results indicate similar hairy fleabane control (94-100%) between 0.4 lb fluridone/ac (about 45 kg/km²), 0.8 lb fluridone/ac (about 90 kg/km²), and flumioxazin 180 DAT (FIG. 31). Additionally, yellow nutsedge control following fluridone applied at every rate was significantly greater than flumioxazin (FIG. 32). Such differences may be due to weed population variability at the Kerman site.

Final evaluations were taken 211 DAT at the Shafter site. Results indicate fluridone applied 0.4 and 0.8 lb/ac provided significantly greater control of hairy fleabane, spotted spurge (Euphorbia maculate), and yellow nutsedge than the 0.1 lb/ac (about 11.25 kg/km²) and 0.2 lb fluridone/ac (about 22.5 kg/km²) (FIG. 33). Further, fluridone appears to have high herbicidal activity on sprangletop (Leptochloa sp.) as control 211 DAT was 88 to 98 percent across the three highest rates of fluridone (FIG. 34). All three rates provided significantly greater control than flumioxazin. This observation was unexpected and surprising, in that among other things, weed control was observed so far after application (DAT) under continuous irrigation conditions.

TABLE 9 Preemergent herbicides, application rates, trial locations, and crops used to evaluate efficacy and crop safety during the growing season. Preemergent Application Rate Trial Location Herbicide (lb ai/ac) (CA) Crop untreated n/a Elderwood orange Kerman almond, grape Kingsburg grape Shafter almond fluridone 0.1 Elderwood orange Kerman almond, grape Kingsburg grape Shafter almond fluridone 0.2 Elderwood orange Kerman almond, grape Kingsburg grape Shafter almond fluridone 0.4 Elderwood orange Kerman almond, grape Kingsburg grape Shafter almond fluridone 0.8 Elderwood orange Kerman almond, grape Kingsburg grape Shafter almond flumioxazin 0.38 Kerman almond, grape Kingsburg grape Shafter almond indaziflam 0.065 Kerman grape Kingsburg grape indaziflam 0.085 Elderwood orange

Example 7 Crop Safety and Weed Control in Grape

Materials and Methods:

Field trials were conducted in California to evaluate tolerance of established ‘Thompson’ grape (Vitis vinifera) to fluridone and the efficacy of fluridone in an irrigated vineyard environment. Trials were placed in grape vineyards located in Kerman and Kingsburg, Calif. The soil in both locations is classified as a sandy loam. Preemergent herbicide applications were made in the month of January in Kerman and in the month of March in Kingsburg. Herbicide treatments in both locations included fluridone applied at 0.1 lb/ac (about 11.25 kg/km²), 0.2 lb/ac (about 22.5 kg/km²), 0.4 lb/ac (about 45 kg/km²), and 0.8 lb/ac (about 90 kg/km²) and flumioxazin at 0.38 lb/ac (about 42.75 kg/km²) (Table 9, supra). Additionally, indaziflam applied at 0.065 lb/ac was included at the Kingsburg site. Rainfall (0.32 in. (about 0.813 cm) in Kerman and 1.5 in. (about 3.81 cm) in Kingsburg) was observed in the first week following PRE application incorporated the herbicides into the soil. Both sites were irrigated as needed during the growing season to avoid drought conditions. Visual evaluations of crop injury and weed control were made monthly on a 0 to 100% scale. Cultivation occurred in the row centers at the Kerman location following the 58 DAT evaluations, and therefore, the Kerman results following 58 DAT were not evaluated. No cultivation occurred in Kingsburg during the trial period.

Results:

Phytotoxicity was not observed following any PRE herbicide application in either location. Weed control following applications of fluridone at rates from 0.2 to 0.8 lb/ac was similar to flumioxazin and indaziflam across all rating dates. In Kerman, no significant weed control differences occurred between the three highest rates of fluridone and flumioxazin. Fiddleneck (Amsinckia Lehm.) control 58 DAT was 98 to 100 percent despite the PRE herbicide applied (FIG. 35). Fluridone applied at 0.2, 0.4, and 0.8 lb/ac provided 13.5 percent greater redmaids (Calandrinia sp.) control than flumioxazin. Canadian horseweed (Conyza canadensis L.) data at the same evaluation date was highly variable (CV=114%). Thus, control differences between fluridone and flumioxazin ranged from 0 to 50 percent depending on rates.

Kingsburg results indicate fluridone at rates from 0.2 to 0.8 lb/ac, flumioxazin, and indaziflam were all effective in controlling barnyardgrass (Echinochloa crus-galli (L.) P. Beauv.), common purslane (Portulaca oleracea L.), and prickly lettuce (Latuca serriola L.) during the 155-day study period. Control of each specie was 94 to 100 percent across all PRE herbicides (FIG. 36).

Example 8 Crop Safety and Weed Control in Orange

Materials and Methods:

A field trial was conducted in California to evaluate tolerance of non-bearing “Cara Cara” orange (Citrus sinensis) to fluridone and the efficacy of fluridone in an irrigated orchard environment. The trial was initiated in the month of January in Elderwood, Calif. The soil on the trial site was classified as a clay. Herbicide treatments included fluridone applied at 0.1, 0.2, 0.4, and 0.8 lb/ac and indaziflam applied at 0.085 lb/ac (about 9.6 kg/km²). Rainfall (0.44 in. (about 1.12 cm)) that occurred in the first week following PRE application incorporated the herbicides into the soil. The site was irrigated as needed during the growing season to avoid drought conditions. Visual evaluations of crop injury and weed density were made on a 0 to 100% scale. Additionally, plant counts per plot of weed species present were conducted for each evaluation period.

Results:

The PRE herbicides applied did not contribute to phytotoxicity during the trial period. Weed control following applications of fluridone at rates from 0.2 to 0.8 lb/ac observed. The two most prevalent weeds on the trial site were witchgrass (Panicum capillare L.) and prostrate spurge (Euphorbia supine Raf.). The three highest fluridone rates and indaziflam resulted in 100 percent control of witchgrass 168 DAT (FIG. 37). Prostrate spurge density decreased as fluridone rate increased resulting in control from 58 to 84 percent. Indaziflam provided 95 percent prostrate spurge control at the same evaluation period. However, no significant control differences for either species occurred between fluridone rates from 0.2 to 0.8 lb/ac and indaziflam during the 238-day trial period (FIG. 38).

Other weeds present on the site included tumbleweed amaranth (Amaranthus albus L.), junglerice (Echinochloa colona L.), and hairy fleabane. Control of tumbleweed amaranth and junglerice increased as fluridone rate increased. The 168 DAT evaluation resulted in 75 to 100 percent control of tumbleweed amaranth and 57 to 100 percent control of junglerice. Neither fluridone nor indaziflam effectively controlled hairy fleabane. Percent weed density was collected 121 and 231 DAT. (FIG. 39).

Example 9 Materials and Methods

An experiment was conducted beginning in the month of August in a greenhouse. The greenhouse was arranged as a randomized complete block with four replicates. A coarse sand soil was used to fill four inch diameter pots. Palmer amaranth (Amaranthus palmeri) seed (100 seed by weight) was evenly dispersed on the soil surface prior to treatment with Fluridone. Fluridone was applied as a surface broadcast spray to each pot at 0.2 lb/ac. Irrigation treatments (0 inches, 0.125 inches (about 0.3175 cm), 0.25 inches (about 0.635 cm), 0.5 inches (about 1.27 cm), and 1.0 inch (about 2.54 cm)) were applied using a sprinkler can immediately following the fluridone application. Overhead irrigation occurred eight and 10 days after treatment, applying an additional 0.25 inch (abou 0.635 cm) of water to each pot. Palmer amaranth control was determined by counting seedlings in each pot weekly.

Results:

The results of this experiment are shown in FIG. 40. Surprisingly, these data evidence that increasing the amount of irrigation increases preemergent control provided by fluridone.

Example 10 Materials and Methods

An experiment with cotton was conducted during the months of April to the month of June in Jackson, Tenn. Plots were arranged as a randomized complete block with four replicates. Plots were 6.3 ft by 30 ft (about 1.92 meteres by about 9.114 meters). The soil on the site was classified as a silt loam soil. Cotton (Gossypium hirsutum) was planted and fluridone was applied as a surface broadcast spray immediately after planting at rates of 0 lb/ac (0 kg/km²), 0.1 lb/ac (about 11.25 kg/km²), 0.2 lb/ac (about 22.5 kg/km²), 0.3 lb/ac (about 33.75 kg/km²), 0.4 lb/ac (about 45 kg/km²), and 0.5 lb/ac (about 56.25 kg/km²). The site received approximately four inches (about 10.16 cm) of rainfall in the first 35 days after treatment (DAT). Visually evaluations of Palmer amaranth control were made twice a month on a 0 to 100% scale.

An experiment with walnut was conducted during the months of December to the month of June the following year in Stockton, Calif. Plots were arranged as a randomized complete block with three replicates. Plots were 8 ft×8 ft (about 2.43 meters by meters)(1 tree/plot). The soil on the site is classified as a clay loam. Fluridone was applied as a surface broadcast spray at rates of 0 lb/ac (0 kg/km²), 0.2 lb/ac (about 22.5 kg/km²), 0.3 lb/ac (about 33.75 kg/km²), and 0.4 lb/ac (about 45 kg/km²). The site received approximately four inches (about 10.16 cm) of rainfall in the first 35 DAT, and an additional 2.9 inches (about 7.366 cm) rainfall and 6.5 inches (about 16.51 cm) irrigation the next 124 days thereafter. Visually evaluations of weed control were made monthly on a 0 to 100% scale.

Results:

The results of this experiment are shown in FIG. 41. These data suggest good control of Palmer amaranth in dryland cotton and good total weed control in irrigated walnut.

Example 11 Control of Weeds in English Walnut

Materials and Methods:

A field trial was performed in a dormant 4th year walnut orchard (Chandler variety) located near Stockton, Calif. The trial was initiated in December for weed efficacy studies and crop tolerance studies. Plots were about 8 feet by about 18 feet (about 2.43 meters by about 5.49 meters) with one tree per plot arranged in a randomized complete block design with three replications. Fluridone, flumioxazin, Roundup, and glufosinate ammonium were tested.

Rainfall and Irrigation data for this trial is summarized in Table 10 below.

TABLE 10 Rainfall and Irrigation data summary. R = Rainfall, I = Irrigation, Irrigation rate was 2 inches of water per 24 hours. Date Inches of water Rainfall or Irrigation December 11 2.21 R December 12 0.52 R December 15 1.20 R December 20 0.75 R February 8 1.06 R March 11 0.15 R April 7 0.51 R May 1 3.5 I May 15 3.0 I May 27 3.0 I June 7 3.0 I June 20 2.5 I Results:

At 19 days after treatment (DAT), all herbicide treatment plots showed 100% weed control, and only the untreated control (UTC) showed any weed population.

At 43 DAT, all herbicide treatment plots showed 100% weed control. Chickweed and Sowthistle were observed germinating in the UTC.

At 88 DAT, field bindweed and annual sowthistle were observed germinating in a plot of the Roundup plus glufosinate ammonium plot and an untreated control plot. All other treatment plots were providing weed control/suppression at >95%.

At 129 DAT, scattered populations of Malva, bindweed, spotted spurge, sowthistle and hairy fleabane were beginning to emerge in certain plots. Some weeds were observed in the plots where the lower rates of fluridone and flumioxazin were applied. Other treatments showed greater than about 90 percent control/suppression.

At 159 DAT, lambsquarter, bindweed, spurge and knotweed were observed in the plots where fluridone was applied at lower rates.

These data show that walnut trees were tolerant to fluridone with no visual leaf symptoms or retarded tree growth with weed control and/or weed suppression.

Example 12 Efficacy and Safety to Stone Fruit Crops

Materials and Methods:

A field trial was conducted in northern California for weed control and safety in one peach orchand and two almond orchards. The herbicide applications were made between January and February when the tree crops were dormant.

Results:

Arbuckle, Calif.; Almond orchard:

Weed control and crop safety were evaluated at approximately 1, 2, and 3 months after treatment. Weed pressure was fairly heavy, and uniform over the trial site. Populations of hare barley, annual sowthistle, black medic, chickweed, and redstem filaree were recorded.

Treatment with fluridone provided excellent weed control, nearly 100% control of all weeds present. Fluridone appeared safe to nonpareil almond, and no phytotoxicity symptoms were observed in the plots at any application rates.

UC Davis, Calif.; Almond Orchard:

Weed control and crop safety were evaluated approximately 1, 2, 3, 4, and 5 months after treatment with fluridone. All treatment rates provided good weed control. Fluridone was safe to nonpareil almond, and no phytotoxicity symptoms were observed.

Marysville, Calif.; Peach Orchard.:

Crop safety was evaluated approximately 1, 2, 3, 4, and 5 months after treatment with fluridone. No phytotoxicitity symptoms were observed in the plots treated with fluridone.

The uses of the terms “a” and “an” and “the” and similar references in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

While the invention has been illustrated and described in detail in the drawings and the foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. In addition, all references cited herein are indicative of the level of skill in the art and are hereby incorporated by reference in their entirety. 

What is claimed is:
 1. A method for cultivating a permanent crop plant with preemergent control of weeds in soil where a permanent crop plant resides, the permanent crop plant being a stone fruit tree, a nut tree, a pome tree, or a grape vine, the permanent crop plant having annual growing seasons that commence with a budding phase of the permanent crop, the method comprising: harvesting crop from the permanent crop plant, the crop grown during a first growing season for the permanent crop plant that occurs in a first calendar year, the harvesting step conducted during the first calendar year; after the harvesting step and during a dormant phase of the permanent crop plant that begins in the first calendar year, applying fluridone to the soil at a rate of about 0.2 pound per acre to about 0.8 pound per acre; and after commencement of a subsequent growing season of the permanent crop plant that follows the dormant phase, irrigating the soil, wherein the irrigating delivers an average of at least 0.1 inch of water to the soil per day over at least a 60-day period taking into account both water provided by irrigation and rainfall and ensures that the soil does not experience any period greater than one week during which the soil fails to receive at least 0.1 inch of water through irrigation or rainfall, so that the fluridone applied during the applying step is effective to provide preemergent control of weeds in the soil for said at least 60-day period during the subsequent growing season of the permanent crop plant, and wherein the crop does not exhibit any symptoms of phytotoxicity from the fluridone as measured by chlorosis, necrosis, or other visual injury to the leaves of the plant.
 2. The method of claim 1, wherein said permanent crop plant is a nut tree.
 3. The method of claim 1 wherein the permanent crop plant is a grape vine.
 4. The method of claim 1, wherein said applying is effective to apply between about 0.225 pounds of fluridone per acre to about 0.35 pounds of fluridone per acre.
 5. The method of claim 1, wherein said method is effective to provide control of fiddleneck, redmaid, horseweed, barnyard grass, common purslane, prickly lettuce, witchgrass, prostrate spurge, hairy fleabane, or yellow nutsedge.
 6. The method of claim 1, wherein the permanent crop is in a region susceptible to glyphosate resistant weeds.
 7. The method of claim 6, wherein said applying comprises spraying a liquid formulation comprising the fluridone onto the surface of the soil.
 8. The method of claim 1, wherein said applying is effective to control the weeds for at least 90 days.
 9. The method of claim 1, wherein said applying is effective to control the weeds for at least 150 days.
 10. The method of claim 1, also comprising the step of diluting a first liquid fluridone composition or dissolving a granule comprising fluridone with an aqueous medium to form said liquid formulation. 